Heres the galley,made a few changes since this pic was taken,added a refrig. Made a hole in the side with a door to access it.
Inside; wallpapered interrior, A/C slides in and out for travel, we bought a futon from Walmart, tossed the frame and used the mattress,fits perfect,folds up into a couch. We used a bamboo mat,cut in 3 pieces,made window shades from 2 of them,then threw the other piece on the floor.

Notice the sat dish. The frame came from Harber Freight, the one with 12" Wheels, foldable,(but not anymore). We used a cheap grade of 3/4" plywood,(all we could afford). Sanded and 4 coats of polly. Cost for the trailer was around $300.00, total cost for all the materials was around $1200.00.