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Fixed Price vs Cost Plus Building Contracts in Sydney: What Homeowners Need to Know

Understand fixed price and cost plus building contracts in Sydney, including risks, inclusions, exclusions, variations, and homeowner protections.

TL;DR A fixed price contract gives more price certainty, but only if the scope, drawings, engineering, finishes, and inclusions are clear. A cost plus contract can work for complex or uncertain projects, but the final price is less certain because the owner pays actual costs plus the builder's margin. In NSW, residential building work must use proper contracts, and projects over $20,000 usually require Home Building Compensation insurance unless exempt. Do not sign any building contract until you understand inclusions, exclusions, provisional sums, prime cost items, variations, progress payments, and delay clauses. Introduction Building contracts are not exciting, but they matter. A bad contract can turn a good project into a dispute. A vague scope can create arguments about what was i…