How to compare two building quotes

Comparing builders on the bottom line is the single most common way homeowners lose money on a build. Two quotes for what looks like the same house can be built on genuinely different assumptions about the site, the inclusions and what is left as an allowance. The gap usually closes during construction, and it closes in one direction.

Put them in the same order first

Builders do not use a common format. Before you can compare anything, rewrite both quotes into the same list of line items. Where one quote has a line the other does not, that is not a saving — it is a question. Most of the real differences surface during this exercise rather than after it.

The five places the difference usually hides

Site costs. One builder has priced the slab off a soil test and a contour survey; the other has used a standard allowance. See what site costs are for what sits in this line.

Provisional sums and prime cost items. An allowance is not a price. Two builders can allow different amounts for the same kitchen and both be reasonable. See provisional sums and prime cost items.

Exclusions. Read the exclusions list before the inclusions list. Driveways, fencing, landscaping, window coverings, letterboxes and clotheslines are commonly excluded, and they are all things you will still have to buy.

Connections and authority fees. Power, water, sewer, stormwater and the council and certifier fees. Sometimes in the price, sometimes a note at the back.

Specification level. Same-looking tap, different tap. Same-looking window, different glazing. This is where a like-for-like comparison takes real work, and where a supplied schedule matters more than a render.

What to ask for so the comparison is possible

Ask each builder for a full specification schedule, the exclusions list in writing, the basis of each provisional sum and prime cost item, and whether the site costs are provisional or fixed. A builder who will not provide these is telling you something useful.

Then compare the contract, not just the price

Two quotes can be identical and the contracts underneath them very different: how variations are priced, what triggers a progress payment, what the delay provisions say. See what is in a building contract.

The honest version of this

Doing this properly takes hours, a spreadsheet and a willingness to ring both builders back with awkward questions. That is exactly the work we do for people, and it is why we exist — but you can do it yourself, and this page is the method.