Most months I sit down with a builder coming off a bad job. The story is almost always the same. The client added work after framing. The deposit got held over a paint touch-up that wasn't on the punch list. The kitchen selections took five weeks. The loan interest ate the margin.
Contractor blogs don't tell that story. They tell the homeowner's story — the slow quote, the missing call back, the dodgy warranty. Both stories are real. This one usually gets left out.
Most of what you need to handle clients like this is already in a standard contract. You just have to write under one that has the right clauses. The other piece is your website. Your website is what filters out the worst clients before they ever sign a deposit cheque.