I went round and round trying to figure out best and easiest way to air condition this bus. I had wanted to use under floor ducting but it got way too compicated. Then I was going to use two units in large plenums to distribute air. Ducting was easier if on top but it was going to be too cumbersome, adding about 6" ht to the install of the AC units.
Finally I decided to do in three zones. Doing this way I won't need ducting to distribute and I think it will work well in the way the space will be used. During the day one would use the two front units and let bedroom warm. Then in evening after dinner one would cool the bedroom and the living room only. And lastly at night only the bedroom unit would run.
I went round and round with manufacturers and unit models as well. I went for one with highest customer ratings that was also rated to be quiet and capable of working on 2 kilowatt generator. Finally settled on the Dometic Brisk II. Although also available in 15k BTU's each, I opted for smaller unit which is only 13.5k BTU's. In total it is about 40k BUT's which will hopefully be impressive.
I picked up three of these for under $500 each, shipped! .... from My12voltstore.com
It was 4.5 out of 5 with 8 reviews there. Amazon had 4 out of 5 stars with over 300 reviews. The Amazon price was $635 each by the time you added the inside control panel. So I saved $400 on the three by not shopping at Amazon (which is pretty rare).