As the car is an 02 plate (same as mine :D ) then it will still have the remainded of the warranty on it. Assuming that your buying the car from a Lexus dealer, if not then you will need to contact them on the following:-
1) If the Alloys are kerbed then they won't be replaced under warranty as it was accidental damage and not a manufacturing fault. If they are corroded or show peeling then they will be replaced FOC.
2) Check for rattles / sqeeks from the interior and seats.
3) Make sure you get the locking nut tool for your alloys!
I made a checklist out when I got mine..e.g. check sunroof ok, check heated seats, check cd player thoroughly, electric seats, you get the drift....
Good luck and enjoy, you'll be passing those :D :D beemers drivers thinking, yer company car is crap.... turn up your hifi and smile....