When I was a kid my dad had a great van/8seater that was getting 30 - 35 MPG all the time, and where
the two rear seats could easily be folded into a double bed. It was a Nissan Serena C23 diesel, Japanese design, incredible slow but extremely reliable and versatile. They were sold in Asia, Europe and Australia, but never in the US I think. It's a shame because it would do well in the eco-modding community ... If import wasn't that difficult you would have something special over there!