I think someone else on this board saw the same car since they also inquired about a brain box. Of course, you don't know what else is wrong w/ the vehicle if the brain box is not working. A very iffy proposition. If you did purchase the car, you could always have the ECU rebuilt, mine ran @$350 at some shop in North Carolina. If you could get the ECU # from the above mentioned vehicle and somehow beg, borrow or steal(just kidding on this one) a matching one, you could plug it in and you would be in a much better position to see if the car is worth $5k. i just saw this add in the classifieds, 85 BMW M6, rare, European, nds brain box, mech special $5000 obo. Surrey... i know i would have to get it checked for other problems, but how much for the brain box should i expect to pay. what else shoudl i worry about. i dont know the mileage either.