I have an electric bed in my toy hauler, came with it. Brand name is "Happi-Jac". They have a website here http://www.happijac.com/
Don't know if it's what you are looking for. If you're going to add the bed, you have a lot of work ahead, and a lot of $$$. My bed is bolted through the outside walls of the trailer with special screws. There is also the wiring. Good Luck., and hope you don't drill a wrong hole.
2012 Ford F250 ext. Cab 4x4
2002 Jeep Wrangler Sahara
2008 Yamaha V-Star 650 Classic
2008 Work and Play 18LT