There are also customizable Class B's - the one that pops into my head is Sportsmobile, who will build exactly what you want as far as layout and amenities goes. Ed and I have a converted Transit-250 cargo van that's more of a "steel tent with a huge comfy bed" - but for our sightseeing wanderlust, it's perfect because it can go on restricted-length roads like the Going-To-The-Sun Road in Glacier NP.