I tried to find the automotive lighting thread, but couldn't Why isn't that stickied in Transportation?
Because it's already in 40% of the threads here? 
A few Car Lighting Tips - Updated
It's nice to know that someone actually wants to read it, though.
I guess the professional photos have professional lighting as well. That's something I will probably never get my hands on.
You already have the proper pro equipment - your eyes. As I said in my thread, "LOOK AT IT" first & find an angle where it looks good. Don't just park it & start shooting.
That might also avoid having a pole growing out of the body as in #s 1, 5, &6.
Good question & tip!
Sometimes you want the sunset behind you to get the right reflections in the car: Some shots of Jim's '68 AMX
Lots to think about. Overall, you gave it a good effort & just need some fine tuning.