slow window regulators
sticking or none working "flick" wipe self parking function on the rear wiper
locks - check central locking from both door locks - dont just rely on the remote locking and this way you can check the locks match the keys too. do the same with the boot in case its had another tailgate and the lock dont match your key. check petrol lock key.
check tail gate pull lever
flick the hazards on.
if its bone dry check the wipers and washers work.
feel along both door bottoms
see if the front windows have up/down scores on em due to grit being jammed in the weatherstrips.
do both rear window hinges open and lock OK? you dont want a floppy one!
signs of rust/leakage around the sunroof.
thing is if you checked this lot and found a problem most of them are easy and cheap to fix anyway.........