Buying New Construction in King County: Builder Contracts & Real Costs

The builder's contract is not the NWMLS form

Large builders use their own purchase agreements, written by their attorneys, and they favor the builder: deposits with limited refund paths, construction timelines that can slide, and materials-substitution clauses. You can still be represented — bring your own agent to the first sales-office visit (builders typically pay buyer-agent compensation, but only if the agent registers you on visit one) and read the contract like it matters, because it does.

Yes, you still need inspections

Municipal code inspections are minimums, not quality control. Hire your own inspector for a pre-drywall inspection (framing, plumbing, wiring visible) and a final inspection before closing, plus the 11-month walkthrough before the builder's first-year warranty expires. New homes routinely have punch lists: flashing errors, HVAC balance, grading that pools water — cheap to fix under warranty, annoying after.

• Ask for the builder's warranty in writing — a common structure is 1 year workmanship, 2 years systems, 10 years structural.
• Verify the builder is a registered contractor with Washington L&I and check complaint history.

Preferred-lender incentives: do the actual math

Builders offer closing-cost credits or rate buydowns for using their affiliated lender. Sometimes it's genuinely the best deal; sometimes the lender's rate is padded enough to claw the incentive back. Get a same-day quote from one outside lender on identical terms and compare the all-in cost over your expected hold. Our mortgage guide covers exactly how to compare lenders apples-to-apples.

Budget for the year-two tax jump and the extras

Early tax bills on new construction are often based on land value or a partial assessment — then jump once the county assesses the completed home. If your first-year escrow was set on the low bill, expect a payment increase in year two. Also budget beyond the base price: landscaping, blinds, appliances sometimes excluded, and lot premiums. New communities can also carry higher local levy rates for new schools and infrastructure.