husker gave you good starters.
adding to that, if you daily drive in traffic, consider the tip. i mainly use mine for recreation but when i run into traffic, i think tip.
get a carfax. if you've got a ppi going the extra doc couldn't hurt. the more info, the better.
talk to the seller; if he/she sounds shaky, they probably are. i talked to one lady selling her boxster and she had the gall to try to explain her way out of her boxster's salvage listing?!?!? ......her number was deleted.
if you do get it, try to keep it around 4.5k rpms. this may generate a gas mileage thread but i read a post here that changed my driving. i used to drive around 3k but the post sort of suggested there's a chance of creating carbon build up in the engine thereby causing engine failure later. looking at the torque/hp chart in the owner's manual it makes sense. the ponies are up in the 5 - 6 k range.
my problems so far:
-rear tires
-oil changes
-2 check engine lites resolving to a new cat converter(free/ warranty!!!)
-driving it too much
whenever you do get it, just enjoy it to the max!! :dance: