How do I check a contractor's variation claim before I pay?

Compare each item with the original scope. Many claims include work that was already in the price.

Look for the instruction. Was it a written direction, an email or a site meeting note? A change you never asked for may not be payable.

Test the price against timesheets, invoices and the rates in the contract. Ask for the backup if it is missing.

Reply within the contract time. Across Australia, state law sets a short deadline for a payment schedule. If you miss it, you may have to pay the full claimed amount. For example, Queensland requires it within 15 business days of the claim, or sooner if the contract says so.