A: body is 100% custom RV body work, current versions look a lot like commercial buses, but in the early days looked like trailers with windshields and steering wheels
B: A stock bodied van built by Ford, Dodge, Chev or recently Mercedes Sprinter. This basic van then has an interior added to it to turn it into an RV
C: A Van nose similar to the vans built into class B but only the nose, sometimes called a cab and chassis that then has a full RV body added to the bare frame at the rear and overhanging the cab.
