The Perfect Estimate: How We Price a Custom Home Without Guessing

Ask ten builders what your home will cost and you’ll get ten numbers — and most of them will be built the same way: square metres multiplied by a rate someone half-remembers, plus a margin nobody talks about.

That’s the industry standard. It’s also how budget blowouts are born, because a number that was never real can’t survive contact with a real build.

We built a different way of doing it. We call it The Perfect Estimate — the estimating process developed at Zanetto Builders that sits behind our 48-hour feasibility and our open-book pricing. It breaks every project into the three things a build is actually made of — labour, materials and subcontractors — and refuses to guess at any of them.

Labour: $20 million of homes, back-costed

Every hour our team has worked on more than $20 million worth of completed custom homes is in a timesheet. We went back through all of it — every task, every home — and extracted the real labour data across 30 labour categories that go into building a project. Framing, cladding, detailed joinery, second-fix carpentry: each category priced from what that work actually took on homes like yours, not what a rate book hopes it takes.

So when we estimate the labour on your project, we’re not predicting. We’re matching your home against a database of finished ones.

Materials: a model of your home, priced from our own price book

We don’t measure quantities off two-dimensional plans, and we don’t hand it to a quantity surveyor working from typicals. Every home we estimate is 3D-modelled by our independent estimating partner, Vision 2 Estimating (V2E). The model gives us the true material quantities — every sheet, stick and square metre — and those quantities are priced against Zanetto Builders’ own SKU codes and live price book from our local suppliers, matched to your region of Tasmania.

Two homes with the same floor area can carry wildly different material costs. A model sees the difference; a square-metre rate never will.

Subcontractors: two quotes, and a tender you can read

For every project we obtain two quotes from every subcontract trade to keep pricing honest and competitive. Then we do something most builders won’t: we run an open-book negotiated tender with you. You see the labour build-up, the material quantities and rates, and every subcontractor quote you ask for.

There’s no “commercial in confidence” between us and the person paying for the home.

And the number most builders won’t say out loud

We go into every project targeting a net profit of 10%. We tell you that before you sign anything, and in an open-book tender you can see how it’s applied.

Why publish it? Because that margin is what keeps the business healthy enough to look after your home — and our team — for years after handover. A builder pricing below a sustainable margin isn’t giving you a bargain; they’re giving you a risk. And a builder who won’t tell you their margin is asking you to fund a number they’d rather you didn’t see.

What this means for your project

• A feasibility within 10% of your real build cost, in 48 hours — because the data behind it already exists
• A Qualifying Budget Estimate if you don’t have plans yet, so you know where you stand before spending anything on design
• A tender where every line — labour, materials, subcontractors, margin — is yours to inspect
• A build that starts from a real number, which is the single best predictor of a build that ends on one

That’s The Perfect Estimate. It took years of back-costing to build, and it’s the reason we can put our accuracy in writing.

Ready to see your number? Start your Perfect Estimate — or read what it costs to build in Tasmania in 2026 first.