So, what do you expect from your rig AC? We have a 13k BTU AC in the front/master and a 15k BTU in the living. At present, the main 15k AC is keeping the rig at 10-12 degrees lower than the outside...
Foil backed bubble wrap insulation on the sunny side windows keeps us chilling in Texas. Home Depot or Lowe's. When not in use we roll it up and hide behind our theatre seats.