Licensed contractors are required by law to provide a written contract for residential work, signed by both parties. Don't rely on verbal agreements. Get all guarantees, warranties, and promises in writing. Limit your down payment or deposit.
Ing to Boundy (2012), typically, a written contract will include: Date of agreement. Names of parties to the agreement. Preliminary clauses. Defined terms. Main contract clauses. Schedules/appendices and signature provisions (para. 5).