Here is a funny story. It was not funny at the time but now I can laugh about it. I bought my 2002 745Li from a showroom in Dammam, Saudi Arabia. It was my first 7 series and I did not know much about it. I test drove the car, it drove fine and the transmission was fine. No errors of the dash so I went ahead and bought it. On the way home I turned on the radio and it sounded awful. Anyway, I got home and got to grips with the car. After a bit of research, I found out that some fool (most probably the Bengali in the showroom) washed the inside of the trunk. That roasted the DVD, GPS, and the in-car movie theater system modules and the in-car telephone modules. I cost me an arm and leg to replace them.