I would personally not buy anything older than '04, you have to remember that it's a high-performance car that has been driven as hard as you can possibly imagine. I have always been told to NEVER buy a used high-performance car.

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2006 BMW X5 4.8is Lemans Blue/Beige/Dark Maple
-Nav, Comfort Seats, Heated Steering Wheel,
Rear Airbags, AUX Input
2009 BMW M3 Space Grey/Black/Carbon
-all options