Thank you for the information, although I don't see that you have asked a legal question. I will assume, for now, that you are asking what your legal options are. I can tell you that it is highly unlikely that the police will help you with this issue. I say that because, for them, it is a civil, and not criminal, issue. Granted, if all of the facts could be proven in a court there could arguably be a criminal fraud or conversion charge, but that is not what the police know when they come to a call. They see two parties disagreeing over money and whether or not there was an agreement. That in turn, to them, makes it it civil issue and they have the option always to decline getting involved. They could, if they choose, at least talk to the guy and tell him he should work this out with you, but that is usually the most they will do.
That leaves your only real legal option if he refuses to give your money back and that is filing suit in small claims court. The process is fairly simply, you do not need an attorney, and you can get the forms from the court clerk in the County where this occurred. When you go to court, you simply explain your side of the story and have your mechanic with you to testify to what they know of the situation. If the court finds in your favor, they award you the money and any court costs and, sometimes, a bit for your time used in pursuing the case. If the other party still refuses to pay after you win in court, then you can go back to court and have the judge issue an order of garnishment and then you can take the funds either through his employer or his bank account.
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