I don't think you can just name a price for a "good" example. It all depends what are you capable to do yourself.
You can buy an 8k dog or you get a decent 4k car which just needs some welding or wear and tear parts.
The condition of the car is important. I have recently seen a black M3 for
sale praised all over from the seller. But he kindly "forgets" to mention that the original engine throw a con-rod out and he has fitted a 2nd hand engine.
Best you examine the car of your choice carefully. Then decide if the price reflects the condition and how much it needs spending on.
Don't forget to check the carpet for wet areas! Front corners. If the screens are misted inside there is a fair chance of rust damage and water is leaking in.
Apart from the rust the old girl is quite robust
