^What he said, but basically an SMB is a camper van. It's a camper, and it's a van. Any RV shop will be familiar with any appliances and maintenance issues you have on the camper side, and any auto mechanic is going to be familiar with a Ford, Dodge or Chevy van. They are about the most common vehicles on the road, especially a Ford van.
Good luck in your search, and don't overthink it. For the money you are considering spending you can get a very nice vehicle, just look at all of the typical items you would look for in a used car, but perhaps have an RV place check out the camper side of things.