currently buying second hand s2 and found a 02 uk model. with 20k on clock and body work in good cond. I am interested. My concern is lifting the bonnet the engine looks particularly grubby and several components look corroded and really tarnished (almost rusty). I am not a mechanic and wondered is this normal or should an engine only 3 years old look pretty clean? I have seem ones of similar age looking perfect -but have they been specially cleaned? maybe I have 'buyiing second hand' paranoia?!! Also alloys have been curbed and are corroding...