How CostMate works for NZ residential builders: where pricing comes from, what's advisory only, and when to bring in a QS or LBP.
An estimating tool is only worth using if you know where its numbers come from and where it hands over to you. Both are on this page.
Every quantity, price, labour hour and code reference in a CostMate estimate is calculated by fixed rules. The AI writes the narrative around them (the scope summary, the assumptions, the exclusions) and it is blocked at the code level from changing a single number.
That is the opposite of asking a chatbot what a deck costs. A model that invents a plausible number is the failure mode this design exists to remove.
CostMate does not sell materials and takes nothing from suppliers on what you buy. The baseline pricing comes from Dayle ITM and PlaceMakers because those are real NZ merchant rates, not because either pays for the position.
You can replace the baseline entirely with your own supplier pricing file, which is the honest answer to the fact that the baseline is Auckland-dated and you may not be in Auckland.
Nothing CostMate produces is a compliance approval. Final member sizes, spans and consent decisions belong to your plans, your designer, an engineer, or your local BCA.
The Quote Checker is trade-only and advisory. It raises checks worth reviewing before you send a quote. It will not tell a homeowner whether a builder's quote is fair, and it is not built to settle a dispute.
CostMate gives you labour hours by phase from your site details and crew size. They are a structured starting point, not a measured NZ average, so set them against what the job takes you and change any line.
Log real hours as the job runs. Your own completed jobs are the only calibration data that means anything for your crew, your region and the way you build, and the reconcile step in how it works puts them next to the estimate.
Treat every figure as a starting point to check against your plans, your rates and your own experience: never as a number to quote from unread.