One trailer manufacturer sells such a model. It has a pop-up solid-roofed room, with interior stairway from the garage below. The "canvas" sides may be un-zipped, converting it to a screen room. I can't remember the brand name, that was last Oct.
2000 Winnebago Ultimate Freedom USQ40JD
, ISC 8.3 Cummins 350, Spartan MM Chassis. USA 1SG, retired;PPA,Good Sam Life member."We the people are the rightful masters of both the Congress and the Courts - not to overthrow the Constitution but to overthrow men who pervert theConstitution. "Abraham Lincoln"