What the contract should say
Washington's Department of Labor & Industries says a contract should include the price with sales tax, the payment terms and completion date, any permit fees, the specific work being done, the materials and major subcontractors, and how warranties and change orders are handled.[1]
Washington also makes contractors issue a separate Notice to Customer disclosure statement once a job reaches 1,000 dollars on a property with four units or less. It has to list the registration number and the bond, and it has to warn you plainly: an unpaid subcontractor or supplier can still put a lien on your property.[2]
When it has to be in writing
California requires a written contract once a home improvement job passes 500 dollars in combined labor and materials, and any change to that contract has to be in writing too, never a verbal add-on.[3]
The payment schedule
Washington's advice is to pay as phases of the work are completed, not on a calendar schedule, and to avoid paying in full until everything is done.[1]
California puts a hard ceiling on the deposit itself: 10 percent of the price or 1,000 dollars, whichever number is smaller, unless the contractor carries a Blanket Performance and Payment Bond with CSLB.[3]
Florida ties the payment schedule to the permit timeline: a contractor who takes more than 10 percent of the price as the first payment has to apply for the permit within 30 days and start work within 90 days of getting it.[4]
Change orders
California's rule against verbal contract changes applies just as much mid-project: never sign a blank or partially blank change order, and put every change in writing before the work happens.[3]
Lien releases, before the final check
Washington's guidance is direct: before you make the final payment, request a completed lien release from every major subcontractor and supplier on the job, since an unpaid sub or supplier can otherwise file a lien against your home even after you have paid the contractor in full.[1]
If you want out
California gives homeowners a three-day written cancellation right after signing a home improvement contract, mailed before midnight of the third day. That window applies on top of, not instead of, whatever cancellation terms the contract itself spells out.[3]
The license number belongs on the page
California requires the contractor's license number to appear on the contract itself, the same as it has to appear on their ads, business cards and bids. A contract missing that number is worth asking about before you sign, and it takes a minute to check that the number matches the business standing in front of you.[5]
Why this matters more in a bathroom
A bathroom remodel touches plumbing and often electrical work inside one small room, which is exactly the combination Washington, California and Florida all single out for extra contract and licensing rules. A deck or a paint job might skip some of this. A bathroom rarely does.