I almost had solar installed when we purchased our AS but backed out at the last minute. Solar made sense for us just for the simple needs of water pump, lights and heater motor so we purchased the 200w ZAMP portable unit that works just fine. In fact probably better than roof mounted unit as we camp in the woods that often lack direct sun so the portable unit allows us to position the panels as best as possible throughout the day.
If we were to start going to those hot places, then AC would become important and we would have to rethink the solar setup. But before we added that I would try to figure out how to better insulate the box. Afterall, don't we try to insulate our homes before we go and add expensive HVAC?
Still perhaps cheaper since we have a trailer is to follow the weather and not need AC: (http://news.justinweather.com/2015/1...ther-all-year/
) which would minimize the need for big solar.