Having had a problem with a contractor with money problems. I would pack it up and run, the bank may shut him down and it will be very hard to reclaim your car. He will probably over run costs and delay if you keep giving money.You are his CASH COW. Find another shop.
My contractor got me for $3600, and is trying to stay out of the license plate factory, class 3 felony, 6-11 years.