Yeah I'm in a similar situation with the 500SEL. It was given to me for free and to date I have put about $5500 in labor and other things that it needed. This includes new tires, new exhaust, and replaced transmission.

I must say that the car runs real good now but it still has some cosmetic things that I don't like. I suppose a full afternoon of attention to it will bring it back up to good condition.

Overall I learned some lessons with this car. It's never a good idea to accept a used and abused luxury car, even if it's for free. Shop around and in the end get what makes you happy.

__________________
1985 500SEL 124k miles
2001 Honda Civic EX