Paint shop Jail...Looking forward to release date.

We had an agreement 16 months ago that he was paid in full. He told me on Monday that if he wanted to he could put a lien on the car because he feels like he should get another $6000.00. I told him " I don't think you want to do that".

Really? Why does he think that? I don't know how the terms of body work goes, but in the mechanic world you get a Repair order with a price, and they call you if the price changes and you authorize the extra work.

Was there no signed agreement in the beginning?