Get the smallest roof AC unit u can get, I think this will be a 9200BTU, not the standard 13,500 BTU that most have. 9200 is plenty for a TC your size.
Agree. The 13,500 will quick cycle once it has initially brought the unit down to temperature. With quick cycling, it doesn't run long enough to bring the temperature down. The 9200 will run more money, but worth it running properly and removing the humidity from the air.
I have a smaller Lance 815 with the 13,500 and have to switch it off, let the camper heat up, then turn it back on. Have to do this so the compressor cycle is long enough for it to remove enough moisture in the air so things don't feel damp. After 14 years of owning this camper, I keep thinking the 13,500 is going to die, but except for a bad capacitor, it just keeps on chuggin.