Here's my #1 pet peeve for taking car photos:
I waited about 20 minutes to get off the perfect shot, judging how the car was rotating and how many people were in my way......but no matter how many pics i took, there was always someone in the way..... happened 50 times or so on that day.
(That was NYIAS 2005 for anyone who's interested. I'm in the process of editing about 75 photos which I'll hopefully get to post later this week.)