Hi Jason,
It is a redundant question, and one there really isn't a solid answer for,
1. Call around in your area, find out what going rates are for local shops, prices differ too much from area to area, and film brands being used. That's why you can't find any threads on "specific" pricing.
2. Decide if you want to price yourself at or above the going rates in your area,
3. figure up on average how much film it's going to cost you to do a vehicle, the 3 brands you listed are all going to be priced diferently in purchasing from the respective dist.
4. you can do a "set" price for 2 door cars, 4 door cars, 2 doors etc etc etc, or you can price each vehicle based on dificulty of the job, entirely up to you.
Good Luck with your adventure