welcome to the club, as gav said mileage doesnt seem to be a major problem on bmws. get one with as much service history as possible though. cant comment on auto boxes im afaid, but like gav id prefer a manual. also check for rust, although not a car that has major rust problems, ive noticed the one place it does usually appear is the wheel arches and on the tailgate were the handle strip is, also on the bonnet around the grille which is prone to stone chips.