2004 bmw 645
Hey all. So I'm in the market for a car and I've stumbled upon the BMW 6 series which I love. I found a 2004 645 coupe with about 71,000 miles on it and will be test driving it soon. It has a clean CARFAX but my only questions are, what problems are soon to come down the road? Any certain mileage reached where problems arise, and when would be my scheduled maintenance and regular services? I've read a lot of good reviews about how reliable these are but I'm curious if it remains even at higher mileage.
Also, how does this 645 compete with say a 2005 SL500 benz? Just wanted to know what to expect! Thanks!