An open floor plan toy hauler with copious amounts of single-pane windows and minimal insulation in the walls and ceiling. It was built in SoCal most likely without regard to those dry camping in 10-20 degree weather and wanting to keep the interior in the upper 60's. The heater ran often enough to deplete the twin batteries daily and required three hours of generator run time to bring them back up for the next night. I could run the 5.5kw generator off the 40 gallon fuel tank with supplemental electric heat, but where we were staying was a state park with set generator hours and dry campsites with no utilities.