I have such a unicorn that I will put up for sale in the next month or so if you can wait. A 2006 E250 5.4 EB50 with only 17,000 miles! It really is like new. Here's the link to the classified ad here when I bought it:
2006 Ford E250 Sportsmobile Value? - Sportsmobile Forum
It was ordered with a lot of options (Starcool, generator, heater, fridge, micro, stove, etc) and the van has the optional limited slip axle. I'm the second owner...first was a handicapped individual, and he ordered it without the rear 3 person folding seat/bed gaucho. He was not able to drive it anymore a couple years after delivery and was only used occasionally by his kids.
Since purchase I removed the handicap equipment and installed a reclinable/foldable three person bench seat in the rear and a single captains chair by the side door to accomodate my kids and two friends. These were from a low mileage Ford Windstar van (upholstery matches the van well) and I installed the factory quick release mounting points. You could have SMB install a gaucho if you want to use the rear as a bed. Right now my kids are small enough to use the rear bed without the gaucho extension.
I also upgraded the wheels to OE Ford forged alloys with new tires. The van had the original 2006 dated tires on it when I bought it with lots of tread still!
I will be selling because I just bought another 2006 SMB...a diesel E350 short body which will be better for an offroad rig. I'd want to get $35,000 as a firm price. Located in Loma Linda, CA. PM me if you're interested.