Dee-
You talk about a house boat.  When I was a kid, my father and a couple of his friends got a bunch of 55 gallon drums, and built a framework and deck around them.  They got an old, small camper, removed the axle, and bolted it to the deck, then mounted a small outboard.  I was just a kid, but I remember it didn't go very fast, but was cool.  Me and my friends would fish while the old man and his friends played cards.  Used to get a lot of stares on the lake.  They had it a few years, then somehow it sank.  I was kind of toying with the idea of building a modern version, if I could get it registered...
Larry