I see. I have question about the Pick-up Trucks.
You guessed right. For those, aside the non-commercial use, must meet the following: A camper top, with one or more side windows completely encloses the truck bed and having seats, seat fittings or camping equipment installed in the truck bed.
Good. Where can i see differences between classes?
You can refer to DMV Regulations and specifically on Part 106 of such rules.