Legal ways to collect your bill for auto repairs?

ScampMike, it can be very hard for a shop owner to recover a judgment in small claims court because the judges tend to be very political and to favor the customer. Most of these judges are elected, and there are a lot more auto repair customers who vote than repair shop owners who vote.
tough thing for sure then... at the very least, the next time someone tried to pick up their car and not pay - - I wouldn't be able to find their keys... for a while, then I would go to lunch or have an "emergency" I had to run off to and deal with.. "oops, sorry, got busy and forgot about you" -- you know, leave them hanging out in the waiting room. Of course they would get the keys back right before closing time - along with a verbal notice that no other work will be performed until the balance of this work is paid in full.