Turnkey vs Build Contract Cost Calculator NZ

This calculator compares the true cost of a fixed-price turnkey home against a standard build contract in New Zealand, so you can see past the headline prices to what each really costs once the extras are counted. The two approaches share out risk very differently. With a turnkey build, you sign up for a fixed price, the builder handles everything, and you pay on completion when you get the keys to a finished house. The price is higher and more certain, and because you only settle at the end, you avoid paying interest on a build loan during construction. A standard build contract usually has a lower base price, but you pay progress payments as the work proceeds, which means interest on the drawn loan through the build, and you typically carry the cost of variations and the difference on provisional allowances, so the final figure is less certain. You enter the turnkey price, then the build contract price, your estimate of likely variations, and the progress-payment interest you would pay, and the calculator totals each path and shows the difference. A standard contract often looks cheaper at first but narrows once variations and interest are added, while turnkey buys certainty. Weigh the cost difference against the value of that certainty. Figures are estimates only and not financial advice.

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A build contract can look cheaper until variations and drawdown interest are added. Turnkey buys cost certainty. Estimate only, not financial advice.