I did not have a Rockwood, but did own an A-Liner, so assuming it would be similar. As far as power, if not hooked up to shore power, it had a battery that would work the lights and the water pump (assuming not hooked to city water either). It had a propane tank that would operate the refrigerator and furnace. Forget about the AC, that required 30amp service.
Regarding ventilation; the unit I had included dormers. These gave large screens on both ends as well as the windows on the sides. Without the dormers (would mean no windows on the ends), ventilation is limited.
2015 Everlite 24RBS
2013 Ford F150 3.5L Ecoboost