John, you may have seen my Volkswagen Van in Key Largo. It´s a diesel, TDI, which I am using since another 4 years now. Just wanted to evaluate a little on the engine:

32 miles per gallon (with a trailer behind), makes more than 100 mph! (I know you cannot run this here in the US). Easily tows a doublestack TIGEr. And it is very clean. Yes, you should polish your boat once in a while but after the trip back from Key Largo to VA Beach, we just rinsed off the "diesel dust".
The van itself will be too small but similar engines are also available in the EUROSPRINTER Mercedes Van, which is sold here as a DODGE SPRINTER. And Airstream (the producer of these silver campers) has the most unique campversion from the SPRINTER on the market here that fits for a family.

Fritz-R. Klocke
VA Beach