Rookie Mistake...

I could see taking the fender tag for restoration purposes, but drilling the dash VIN would have pissed me off royally and sent a red flag you were in the wrong place with it. Report that to the police and tell them you would like some assistance in retrieving it? Take your proof of ownership to the police as well. I don't know if this applies in other States but in Ma. it is legal to charge any price per hour for restorations and if you sign a contract for any amount per hour you are bound to pay it. Lesson learned? Always get a contract. As said, best is to supply material and make payments with it stated in your contract you can remove vehicle at any time so long as payments were paid up.