I called a licensed contractor in Maryland to set up an appointment for an estimate. The next day the contractor came and determined the problem. The contract said could be fixed immediately.
I agreed and the contractor fixed the problem after 4 hours. Price was never discussed and no written contract or estimate was executed.
From a legal perspective, how much if any amount, do I need to pay?
This is a common situation but I could not find an answer searching the internet.
You need to pay a fair price. It's not easy to determine what that amount is, but the primary considerations from a legal perspective would be his hourly rate, how long it took, and what the materials costs were. The difficulty of the job might also be relevant. If you are charged $1,000 and other contractors would charge around $800 for that, the $1,000 charge is not shocking: if others charge $200, then (unless somebody is omitting material considerations in their bid, e.g. "that guy is not licensed; he uses below-code materials") you might have an argument that the charge is more than you would have agreed to.
