If your bus sits outside every day and the sun beats thru the windshields (makes it like an oven inside, right?) here's an inexpensive tip that really helps- get a peice of foil backed insulation Celotex type product in the 4x 8 sheet and block the bus windsheilds with it. EZ-Hold the wiper blades back and slide it in place. (outside of windshield) It will rest on the wiper shafts and release the blades and they will hold it in place. I'll post a pic of mine today. You will not beleive the heat that it relects back. It will make a big time difference in the interior temp of the bus. It did make a lot of difference when I had my curtains in place that I could close to block the sun, but the celotex outside works even better. Of course, its not something that would be recccomended at the campground tho........
One caveat however, the celotex is unsightly, but my bus can't be seen from the road or neighbors house anyway.
reduce heat for $10........what a deal!