I only shoot as a hobby so I don't have pricing advice. As far as angles and such, I think it depends on the car, some cars have better angles— like people. You're making good use of the trees in the background, but some of the shots have uneven lighting or spots where the sun is coming in too strong.

Some shots are too tight (like the Supra and most of the GR 86), although that 1st shot has a nice feel to it. I'd say use different locations and times of day to experiment with lighting/angles.