It depends on where the car is located I guess, sometimes you are limited to what angles you can take pics at.
I generally take pics from different angles and heights, sometimes the camera is on the floor and looking up at the car and sometimes its high in the air.
Also, its good to look for somewhere to stand to get a 'different' view of the car - for example I love being able to stand somewhere I am above the car and can shoot down on it.
The tripod is only used in low light situations for me.....to much of a hassle to be used for all pics (and not needed).
Hope that answers your question....
EDIT: one of the most important things for me is that the whole car is in the shot, and the front or back is not 'chopped' off. (unless of course your taking detailed shots).