looking at picking up an 02'
#1
#2
check the balljoints on the front, if they have been changed they will be bolted on, also rear liftgate rust, if it has the 5.9 and higher mileage make sure it has the trans service records, if it has the 4.7 its still a good idea, but not as vital, other than that just the normal stuff to check on a used car purchase
#3
I have an 02 myself and absolutely love it. I have the 4.7L and it has plenty of power. The only thing I think you should check is the ball joints like shrpshtr said and check the rack and pinion for leaks. Other than that make sure the A/C is issue free because those repairs can get costly. Good luck with the trade, post some pics when you get it!
#5