Help with 89 735i

I just bought a 1989 735i with 241k miles on it and my wife is mad because she thinks its junk. I need to know if there are any known issues with BMW, as this is my first, that I should know about.
Im taking it in for a checkup today and if there is major issues, I wont buy it. For $600 is it really going to hurt?

should watch out, bimmers have a tendency for electrical problems that can run you just as much as the car is worth sometimes.

I had a question on a 94 740il any thing that I should look out for? It has 175,113 miles on it and its from a little dealer. I know the cooling system has to be flushed and check to see if the tranny has been changed or rebuilt but anything other than that? Thanks