Granny Flat Costs NSW 2026 - Get Free Quotes

Granny Flat Costs in NSW

A one bedroom granny flat built on site runs $120,000 to $180,000 across New South Wales, a two bedroom of around sixty square metres $150,000 to $220,000, and a prefabricated or modular unit $95,000 to $180,000 before craneage. Kit packages supplying materials without labour cost $40,000 to $90,000. Site costs add $15,000 to $60,000, approvals and certification $3,000 to $8,000, and service connections $5,000 to $25,000 depending on distance. On a per square metre basis, most completed projects land between $2,200 and $3,500. Those bands assume a licensed builder delivering a completed dwelling rather than a supply only arrangement. Where a figure sits inside them depends far more on the block than on the design.

The gap between an advertised price and a finished project is the thing to understand before anything else. Builders market a starting figure that covers the dwelling itself, delivered to a level, clear, accessible site with services at the boundary, which describes very few real backyards. Everything else appears as site costs, provisional sums or exclusions, and those items regularly add thirty to sixty thousand dollars. A quote that looks twenty thousand cheaper than the others usually excludes twenty thousand more.

New South Wales is the easiest state in the country to build a secondary dwelling, which is why so many are built here. A dedicated planning pathway lets a compliant granny flat be certified rather than assessed, which turns a process measured in months into one measured in weeks. That advantage is real, and it does not remove the need to understand what the finished project will cost. Broader construction scope sits under granny flat construction. Around twenty thousand secondary dwellings have been approved across the state over the past decade, which has produced a builder market with genuine depth.

Build Price Against Finished Project Cost

The build price covers the dwelling as a structure, meaning the slab, frame, roof, cladding, windows, internal linings such as Gyprock, the kitchen, the bathroom and the standard fixtures a builder includes in their base specification, where Rheem or Rinnai hot water and Caroma tapware are the usual assumptions. It assumes a straightforward site and standard conditions, and it is the number used in advertising because it is the lowest defensible figure. Nothing about it is dishonest, and it is also not what you will pay. Treat it as the starting point of a budget rather than the budget. Compare inclusion lists line by line rather than comparing headline figures, since two builders quoting the same number may be offering quite different dwellings.

Site costs are the first addition and the most variable, covering excavation, cut and fill on a slope, retaining where levels change, rock removal, additional footings where the soil demands them, and access provisions where machinery cannot reach the build area. On a level block close to the street these are modest, and on a sloping rear yard reached through a narrow side passage they are substantial. No builder can quote them accurately without a survey and a soil classification. Some builders present these as an allowance and reconcile the difference later, while others price them fixed after investigation, and knowing which you have matters. Ask which of the two approaches a builder is using before you compare their number with anyone else's.

Approvals, certification and consultant fees follow and are reasonably predictable. A complying development pathway involves a private certifier, a site survey, a soil classification report, and a set of stamped plans, which together run $3,000 to $8,000 in most cases. A development application to council costs more and takes considerably longer. Either way these are professional fees rather than construction, and some builders include them while others do not, which is a common source of confusion when comparing. Engaging your own certifier rather than accepting the builder's is an option worth considering, since the certifier's role is to check the work rather than to facilitate it.

Service connections are the item owners most often forget entirely. Water, sewer, electricity and stormwater all have to reach the new dwelling, and the cost depends almost entirely on how far the granny flat sits from existing connection points and what lies between. Twenty metres across a lawn is inexpensive, while the same distance under a driveway, around a mature tree and through rock is not. Sewer in particular can require a specific connection arrangement and authority approval.

External works finish the picture and are excluded from almost every advertised price. A path to the front door, a driveway or parking space where one is required, fencing to separate the dwelling, a clothesline, a letterbox, turf and basic landscaping all cost money and are all necessary before anyone moves in. Budget $8,000 to $30,000 depending on how much is needed. Surfacing and driveway work is quoted at driveways and paving. Parking requirements in particular catch people out, since a council may require a space for the secondary dwelling and creating one is not free.

Approval Pathways in New South Wales

Two pathways exist for a secondary dwelling in New South Wales and the difference between them is substantial. The complying development pathway allows a proposal meeting all the prescribed standards to be certified by a private certifier or council without a merit assessment, typically within weeks. A development application is a merit based assessment by council for anything that does not meet those standards, and it takes months rather than weeks and costs more in fees and consultants. Neither pathway is a rubber stamp, and both require the finished dwelling to meet the building standards that apply to any home. Which one applies is determined by your land and your design rather than by preference.

Complying development is only available where every relevant standard is met, and failing a single one pushes the proposal to a development application. The criteria have historically covered minimum lot size and width, maximum floor area, setbacks from boundaries, site coverage, landscaped area and the requirement that the secondary dwelling sit on the same lot as the principal dwelling. Numbers attached to these have been amended more than once in recent years, which makes current confirmation essential rather than optional. A designer who works with the pathway regularly will shape a proposal to fit rather than designing something that then fails a criterion.

Because the rules have moved, the sensible approach is to have a certifier or a designer confirm what applies to your specific property today rather than relying on figures from a website or a neighbour's project. Planning information and property services are accessible through Service NSW, and a certifier will tell you within a short conversation whether your block qualifies. That call is free or inexpensive and it determines your entire timeline. Councils also publish local provisions that can affect the outcome, so a quick check of your own council's position alongside the state rules is worthwhile.

Constraints on the land itself can rule out the fast pathway regardless of block size. Heritage listing or a heritage conservation area, bushfire prone land, flood affected land, land with significant trees subject to council protection, and easements running through the proposed building area all complicate matters. Some of these mean a development application, and some mean additional reports rather than a different pathway. Rules specific to this state are set out under granny flat rules.

Approval is not the end of the process, since the certifier remains involved through construction with mandatory inspections at defined stages and an occupation certificate at completion. Nobody may lawfully occupy the dwelling until that certificate is issued, which matters if you have a tenant lined up. Allow for that gap in the timeline instead of assuming the keys and the certificate arrive together. The certification route is covered under granny flat complying development and approvals generally under granny flat approval. Keep every certificate and inspection record with your property documents, since a future buyer's conveyancer will ask for them.

What Site Costs Actually Cover

Soil classification is the starting point and it determines the footing design before anything is dug. A geotechnical report classifies the site according to how reactive the soil is, and reactive clay across western and south western Sydney and parts of inland New South Wales requires deeper and stiffer footings than sand or rock does. The difference between a stable classification and a highly reactive one can be tens of thousands of dollars in slab cost alone, and it is not negotiable. The report is inexpensive relative to what it prevents, and any builder pricing footings without one is guessing at your risk. Classifications are set out in the Australian Standard covering residential slabs and footings published by Standards Australia.

Slope drives cut and fill, retaining and drainage. A fall of half a metre across the building footprint is manageable, while anything steeper means excavating into the hill, retaining the cut, and dealing with where the water now goes. Retaining walls above modest heights need engineering and add cost quickly. On the steepest sites a suspended floor on piers is cheaper than trying to create a level pad, and a good builder will raise that option early. Retaining walls also need to be included in the approval documentation rather than added afterwards as an afterthought.

Rock is the Sydney speciality and it deserves specific budgeting. Sandstone sits close to the surface across large parts of the city, and hitting it during excavation for footings, trenches or a driveway multiplies the cost of that work several times over. It cannot be reliably predicted from the surface, which is why a geotechnical investigation matters and why rock is frequently handled as a provisional sum rather than a fixed price. Earthworks and any site cut are priced separately under excavation.

Access determines what machinery can reach the build area, and on a rear yard granny flat it frequently determines the method of construction. Where a truck and excavator can reach the site, work proceeds normally. Where the only access is a side passage under two metres wide, material is barrowed, small machines are used or the neighbours are asked about temporary access, and every one of those adds days. Measure your narrowest point before you talk to anyone. Where access is genuinely tight, discussing it with builders early lets them propose a method rather than declining to quote.

Trees and vegetation complicate site works more than owners expect. Council tree controls apply to the granny flat site as much as anywhere else, root zones of protected trees restrict where footings and trenches may go, and an arborist report is frequently required as part of an application. Removing a tree to make room is not automatically permitted. Assessment of that kind sits under arborist reports. Root zones extend considerably further than the canopy suggests, which surprises owners planning to build close to a boundary tree.

Site Built, Modular or Kit

Site built construction is the conventional route and remains the most flexible. A builder constructs the dwelling in place using the same trades and sequence as a house, which allows the design to respond to the block, accommodates awkward shapes and slopes, and lets you change specification during the build. It costs $120,000 to $220,000 depending on size and finish, takes three to six months on site, and suits any property a builder can access. It also handles the awkward realities of an established backyard better than a factory built unit can. Staged payments follow completed work, which spreads the outlay across the programme.

Modular and prefabricated construction builds the dwelling in a factory and delivers it in one or more sections to be craned into position. The advantages are speed on site, weather independence during construction, and a fixed factory built quality. The constraints are that the site must be accessible to a truck and a crane, the design comes from a range rather than being drawn for your block, and craneage plus traffic control adds $3,000 to $12,000. Factory built routes appear under modular granny flats. Payment structures differ as well, with more of the money paid before anything arrives on site, which is worth understanding before signing.

Kit packages supply the materials and the plans and leave the labour to you or to trades you engage directly, at $40,000 to $90,000. On paper this is dramatically cheaper, and in practice the saving depends entirely on whether you can genuinely manage a residential build. Someone with construction experience and time can do well from it, while someone learning as they go frequently spends the difference on delays and rework. Products of this kind sit under granny flat kit homes.

Owner building is the decision underneath the kit option and it carries real obligations in New South Wales. An owner builder permit is required for work above a prescribed value, the permit holder takes on responsibilities normally carried by a licensed builder, and there are consequences at resale including disclosure requirements and warranty obligations that follow the property. It is a legitimate route for the right person and a serious commitment rather than a shortcut. Insurance obligations differ for owner builders as well, and warranty responsibilities can transfer to you rather than sitting with a builder.

Comparing methods on price alone misses the differences that matter afterwards. A site built dwelling designed for your block can be positioned to suit sunlight, privacy and the existing house, while a modular unit arrives as designed and sits where the crane can place it. Both produce good outcomes when matched to the right site. Design options are covered under granny flat designs and layouts under granny flat floor plans. Visit a completed example of each where you can, since half an hour inside a finished dwelling tells you more than a brochure.

Water, Sewer, Power and Stormwater

Every service reaching the new dwelling costs money proportional to distance and difficulty, which is why position on the block affects the budget as much as size does. A granny flat sited close to the existing house shares short runs for water, sewer, power and drainage, while one placed at the rear boundary for privacy adds every one of those runs at full length. That trade off between amenity and cost is worth making deliberately rather than discovering it in a quote. Running services in a single shared trench where the authorities permit it reduces the cost compared with separate runs. Mark the intended position on the ground before finalising it, since twelve metres reads differently in a backyard than on a plan.

Sewer connection is usually the most involved and the most expensive. The new dwelling must connect to the sewer in an approved manner, which may mean extending the existing line, and where the sewer main runs through or near the property there are restrictions on building over or near it. Building over a sewer main requires specific approval and engineering. Work on an existing line sits under sewer line repair.

Electrical supply raises a question owners rarely anticipate, which is whether the existing service to the property can carry the additional load. Adding a second dwelling with its own kitchen, hot water and air conditioning to a house already at capacity may require a switchboard upgrade, a larger supply, or a supply upgrade coordinated with the network operator. That is worth checking early because it is expensive and it has a lead time. Switchboard work sits under switchboard upgrade. Solar and battery arrangements also need thinking about at this point rather than later, since the switchboard work overlaps.

Metering arrangements need deciding and they affect how the dwelling is used. A separately metered granny flat lets a tenant be billed directly for electricity, while a shared meter means the arrangement is settled between you and the occupant. Separate metering costs more to install and is generally worth it where the dwelling will be rented to someone outside the family. Water is typically not separately metered on a secondary dwelling, which is worth knowing before setting a rent. Whichever arrangement you choose, set it out in the tenancy agreement so there is no argument about it later.

Stormwater has to be dealt with properly and it is a common cause of trouble later. Roof water from the new dwelling needs a legal point of discharge, which usually means connecting to the existing stormwater system or to the street, and the additional hard surface can overload a system already at its limit. On a low lying or flat block this may need an absorption system or a pump. Drainage work sits under stormwater drainage plumbing. Directing water toward a neighbour rather than to a legal discharge point creates a dispute that is expensive to resolve.

Title, Value and Finance

A secondary dwelling in New South Wales remains part of the same lot as the principal dwelling and cannot be separately sold, which is the single most important thing to understand about the investment. You are not creating a second property, you are adding a building to the one you own. That distinction affects how lenders treat it, how it is valued, and what happens when you sell, and it surprises a proportion of owners every year. Dual occupancy development is a different proposition entirely and does allow separate titles in some circumstances, which is worth exploring if separate sale is the goal. That single fact reshapes the financial case for many households once they understand it.

Valuation of a property with a granny flat is not a simple addition of the construction cost. Valuers assess what the improved property is worth in the market rather than adding the build cost to the previous value, and the uplift is frequently less than the amount spent, particularly at the higher end of specification. In areas with strong rental demand the income supports a stronger valuation, and in others the second dwelling adds less than it cost. Rental considerations sit under granny flat rental income.

Finance usually comes from equity in the existing property rather than a separate loan, since there is no second title to secure. Construction lending against the existing property is the common structure, with funds released in stages against the builder's progress claims. Lenders assess the finished value and the borrower's capacity as they would for any renovation, and some treat expected rental income from a granny flat conservatively. Speak to a lender before signing a building contract rather than after. Progress payment schedules need to align with what the lender will release, and a mismatch between the two causes real problems mid build.

Rates, insurance and holding costs all change once the dwelling exists. Council rates may be affected, building insurance needs to cover the additional structure, and landlord insurance is a separate product if the dwelling is tenanted. Land tax may become relevant depending on your circumstances and the property's use. None of these is large individually and together they change the return calculation, so include them rather than modelling rent against construction cost alone. Getting tax advice specific to your situation is worthwhile where the dwelling will be rented, since the treatment affects the return materially.

Tenancy of a secondary dwelling is subject to the same residential tenancy framework as any other rental in New South Wales, which means a tenancy agreement, bond lodgement, repair obligations and the notice provisions that apply to any landlord. Renting to a family member informally is common and still creates a legal relationship worth documenting. General consumer and tenancy information is published by NSW Fair Trading. Renting to family without an agreement is the most common arrangement and the one that causes the most difficulty when circumstances change.

Contracts, Insurance and Progress Payments

Residential building work in New South Wales above the prescribed value must be carried out under a written contract by an appropriately licensed builder, and a granny flat is well above that threshold. The contract should specify the work, the price, the payment schedule, the timeframe, the specification and what happens when something changes. Licence status can be verified with NSW Fair Trading before you sign anything, and it takes a minute to check. Check that the licence class actually covers the work being done, since licences are issued for defined categories. Verbal agreements have no place in a project of this value, however well you know the builder.

Home building compensation cover is a requirement for residential building work above a prescribed value in New South Wales and it protects you if the builder dies, disappears or becomes insolvent, or fails to rectify defective work in defined circumstances. The certificate must be provided before you pay a deposit or work commences. Ask to see it rather than assuming, since a builder unable to obtain cover is telling you something important about their financial position. The cover has limits and conditions rather than being unlimited protection, so read what it actually provides.

Deposit and progress payment limits apply and exist to protect you. There are legal caps on the deposit that may be taken for residential building work, and progress payments should be tied to completed stages rather than to dates on a calendar. A payment schedule weighted heavily toward the early stages leaves you exposed if the builder stops, which is the situation the rules are designed to prevent. Read the schedule carefully before signing. Never pay ahead of the stage being completed, however reasonable the request sounds.

Variations are where budgets move and they need controlling in writing. Any change to the scope, whether requested by you or arising from site conditions, should be documented with a price before the work is done rather than appearing on a later invoice. Provisional sums for rock, footings or connections should state what has been allowed and how the difference is settled. Your rights to services supplied with due care and skill are consumer guarantees overseen by the ACCC. Keeping a simple log of every variation with its date and price gives you a running total rather than a surprise at the end.

Safety obligations on a residential building site sit with the builder and are administered by SafeWork NSW, which matters to you because the site is your backyard and your household is around it. Fencing, exclusion from the work area and site tidiness are legitimate things to raise. Where a granny flat is one part of larger works, wider scope sits under home extensions. Where children or pets use the yard, agreeing the site boundary and fencing before work starts is a reasonable request.

What Drives the Price

Site conditions produce more variation than any design decision. How reactive the soil is sets the footing, a fall brings cut, fill and retaining, and rock decides whether the dig is ordinary or costly. Two identical dwellings on two blocks in the same suburb can differ by forty thousand dollars purely on what is under and around them, which is why a fixed price offered without a survey and a soil test is an estimate wearing a fixed price label. This is also why quotes from builders who have visited the site are worth more than those from builders who have not.

Size and configuration set the base and the relationship is not linear. A second bedroom adds structure, roof, a window and frequently a second bathroom, so the step from one bedroom to two costs more than the extra floor area suggests. Compact well planned layouts deliver more usable space per dollar than larger inefficient ones. Comparative figures sit under one bedroom granny flat costs and two bedroom granny flat costs. Ceiling height, roof form and window count all move the figure as well without changing the floor area at all. Efficiency of layout is where a good designer earns their fee on a small footprint.

Specification is where owners lose control of a budget without noticing. Over a modest floor area, stone rather than laminate on the bench, a better bathroom, timber underfoot rather than vinyl, higher ceilings and upgraded joinery each seem modest and together add twenty to forty thousand dollars. Decide the specification before signing rather than during construction, when every change is a variation priced without competition. A standard inclusions list is worth reading line by line. Ask what the standard inclusion actually is for each item rather than accepting a general description of quality.

Distance from the existing house drives service connection costs directly. Every metre of trench for water, sewer, power and stormwater is charged, and running those services under a driveway, around a protected tree or through rock multiplies the figure. Siting the dwelling twelve metres from the house rather than thirty saves real money, and it needs weighing against privacy and how the yard is used. Position is a cost decision as well as a design one. Privacy can often be achieved with screening and orientation rather than distance, which is considerably cheaper.

Timing and market conditions affect what builders quote in ways outside your control. Trade availability, material prices and how busy the builder is when you ask all move a price, and quotes obtained in a busy period are higher than the same work in a quiet one. Getting three quotes matters more in this trade than most, given the sums involved. Choosing between them is covered on the granny flat builders hub. A builder quoting well below the others is worth questioning rather than celebrating, since the difference is usually scope.

Granny Flat Costs Across Sydney

Sydney has the deepest concentration of granny flat builders in the country and genuine competition on standard designs. Block characteristics are what separate one part of the city from another, since soil, slope, rock and access differ enormously between the sandstone country of the north and east and the clay plains of the west, and those factors move a project cost far more than any suburb premium does. Visiting a builder's completed projects in your area is straightforward here in a way it is not everywhere, and worth doing before shortlisting through granny flat builders. Ask to see one at least a couple of years old rather than a brand new handover, since that is where workmanship shows. Speaking to the owner while you are there is usually more informative than anything a sales office will tell you. Three quotes is the minimum worth obtaining given the sums involved here.

Western and south western Sydney is where the majority of granny flats in this state are built and the reasons are structural. Lots tend to be bigger and clear the minimum area comfortably, sitting flat with uncomplicated access for machinery, rental demand is strong, and builders operate at volume in those areas which keeps pricing competitive. Reactive clay is the local complication, since it drives a stiffer footing design than a sandy or rocky site would need. Rental returns in these areas are also the reason many of these projects proceed, and local agents can give realistic figures for your street.

The north shore, northern beaches and eastern suburbs produce the most expensive projects in the state, and the causes compound rather than simply adding. Sandstone close to the surface makes every excavation dearer, slope means cut, fill and retaining, rear yards are frequently reachable only through narrow side passages, established trees carry council protection, and heritage conservation areas cover substantial parts of these suburbs. Expect a longer approval process and a site cost figure at the top of the range. Modular construction is frequently impossible in these suburbs because a crane cannot reach the rear yard.

Granny Flat Costs in Regional NSW

Freight, trade availability and lead time rather than hourly rates are what change once you move beyond Newcastle, the Hunter, the Central Coast and the Illawarra. Those four areas support established granny flat builders and price much as Sydney does. Further out, fewer specialist builders operate, general residential builders take on the work instead, materials are freighted, and scheduling around other commitments extends the programme. Lead times stretch further from the city, where capable builders fill their calendars early. Grouping the granny flat with other planned work on the property can make a builder's trip worthwhile.

Rural properties change the calculation because services cannot be assumed. A property on tank water, with a septic or aerated wastewater system and no sewer connection available, needs the secondary dwelling integrated into those systems or given its own, and an existing wastewater system sized for one dwelling frequently cannot take a second. That assessment comes before the build rather than during it, and it can add materially to the budget. A wastewater consultant rather than a plumber is usually the right first call on these properties.

Planning on rural and semi rural land differs from residential zoning and the fast pathway may not apply. Minimum lot sizes, zoning provisions and the way a secondary dwelling is treated on rural land are not the same as in a suburban street, and some rural zones handle secondary dwellings quite differently. Confirm the position for your specific zoning before committing to a design. The criteria themselves are covered under granny flat rules.

Bushfire prone land affects a great deal of regional New South Wales and it changes both the approval and the construction. A property with a bushfire attack level rating requires the dwelling to be built to a corresponding construction standard, which affects windows, cladding, decking, screening and sealing, and it adds cost that scales with the rating. A bushfire assessment forms part of the application on affected land, and it is worth establishing your rating early. The rating depends on vegetation, slope and distance rather than simply on whether the area has burnt before.

Modular construction often makes more sense outside the cities than within them. Where local trades are stretched and a site built programme would run many months, a factory built unit delivered complete can be a better answer, provided the transport route and crane access work. Access assessment matters more on a rural property with a long unsealed driveway than it does in a suburb. Comparative pricing sits under prefab granny flat costs. Delivery access along a long unsealed driveway needs assessing properly, since a truck carrying a completed dwelling is a substantial vehicle.

What to Look Out For

Establish what each price excludes before comparing anything. Advertised build prices assume a level, clear, accessible site with services close by, and the items outside that assumption regularly total thirty to sixty thousand dollars. Ask each builder for a written exclusions list covering site works, approvals, connections, external works and any provisional sums. The cheapest headline figure is frequently the most heavily excluded one, and that becomes apparent only after you have signed. Put the exclusions from all three quotes side by side, since the differences between them are the real comparison. This single step prevents the majority of budget overruns on these projects.

Be wary of a fixed price offered without a survey and a soil classification. Nobody can price footings without knowing the soil, and nobody can price excavation without knowing whether rock is present, so a fixed price given from a street view and a floor plan has assumptions inside it that will surface later as variations. A builder who insists on the investigations first is protecting both of you rather than delaying. Commissioning the survey and soil test yourself, then circulating identical reports, is what makes quotes comparable.

Confirm the licence and the insurance certificate before paying anything. Residential building work above the prescribed value requires an appropriately licensed builder, a written contract and home building compensation cover, and the certificate must be provided before a deposit is taken. Verify the licence yourself rather than accepting a number on a letterhead. A builder who cannot obtain cover is a builder whose financial position an insurer has already assessed.

Understand that you are not creating a second property. A secondary dwelling in New South Wales sits on the same title and cannot be separately sold, so the return comes from rental income and whatever valuation uplift the market gives, not from creating a saleable asset. Model the investment on that basis rather than assuming the spend is recovered. Anyone whose plan depends on selling the granny flat separately should look at dual occupancy or subdivision instead, and weigh the income case through granny flat rental income.

Check the constraints on your land before falling for a design. Heritage listing, a conservation area, bushfire prone land, flooding, protected trees and easements can each rule out the fast approval pathway or add requirements, and finding out after you have paid for plans is an expensive way to learn. A certifier or designer can confirm the position for your property quickly, and the earlier that happens the better the whole project runs. A pre-purchase check matters too if you are buying a property specifically to add a granny flat.

What to Look for in a Quote in NSW

Two builder quotes are only comparable once both cover the same scope, which is rarely the case without asking. A useful quote states the dwelling size and configuration, lists the standard inclusions specifically enough to compare, sets out what site works are allowed and on what basis, says whether approvals and certification are included, states the service connection allowance, covers external works or explicitly excludes them, and identifies every provisional sum. Site works and connections are the lines that separate an honest quote from an optimistic one. Ask for the quote to be structured the same way by each builder if you can, since that alone makes the comparison possible. Anything vague at quoting stage will be resolved in the builder's favour once work is under way.

Put the same site information in front of every builder so the responses mean something. Give the block dimensions and area, the approximate fall across the proposed building area, the width of the narrowest access point, the distance from the existing house to the intended position, whether you know of rock or fill, and any trees, easements or overlays you are aware of. A copy of your survey plan, if one exists, answers most of it at once. Current photos of the intended footprint taken from several positions help too, especially any showing how machinery gets in route.

A builder who wants a survey and a soil test before firming a price is being straight with you. Someone who asks about access width, wants to know where the sewer runs, raises tree protection and explains how rock would be handled has built granny flats on real backyards. A number produced from a floor plan and a suburb has assumed a site nobody has looked at, and the assumptions will be corrected at your expense during construction. Put the rock scenario to them directly, since the answer separates a builder with a method from one with a hope.

Settle the scope, the exclusions, the contract and the payment schedule before signing. Get the exclusions in writing, agree how provisional sums are reconciled, confirm the licence and insurance certificate, check the deposit and progress payment structure against the legal limits, and fix the specification before work starts rather than during it. Only then is it worth approaching your lender with a figure. Builder listings sit on the granny flat builders hub, with the state overview under granny flats in NSW.