88' 750iL problems?

I am in the market for an E32 735iL or 750iL for my first car and was after any information about common problems and what i should look out for, there are a couple of areas which concern me as to the problems and price for repairing it eg. Auto-Leveling Suspension.
I am looking for any information about any problems you may or may not have had because as you can imagine as a first car i want something i do not have to put all of my money into to keep it on the road, i understand that regestration, insurance and servicing will be up on the 750 as compared to say the 735 or a smaller car even.
I have done a lot of reaserch and i know all about the fuel consuption and stuf like specs and all, all the normal stuff.
In the following list i have made, i wanted to know if anyone has experieced any problems with the following;
Auto-Leveling suspension (how does this work by the way) The electric seats (the one i am looking @ has them front & rear) Limp home mode (what causes it and how does it work) Any other engine problems (mechanical or electrical) Any probs with the auto box (4speed std) OBC failure or fault if you have expirienced any other problems could you please tell me because i dont want to buy a car and overlook some important and expensive aspects. I plan on taking it to a dealer to be checked over of course.

But if you can give me any information regarding any problems please,
it will help me a great deal and may save me lots of money.