Today the forecast was for 124*, it actually hit 125*!
Here is my indoor/outdoor thermometer reading...
Thermometer is at elbow level next to couch.
These are real numbers folks...
I didn't hold it next to the A/C outlet or put it in the fridge.
I have been achieving similar numbers here in the Arizona desert for the last 15 years, last 2 summers in the SP34T toyhauler (pictured in sig) that we have now, the previous 9 years in a 1976 Holiday Rambler Presidential 3300 TT (30' w/ single 15,000 btu), and the first 4 years in a 1972 24' Dodge class A w/ single 15,000 btu A/C.
Turn your RV into a cave, put tight-fitting Reflectix reflective insulation in all windows, vents and skylights. Keep A/C(s) set at 80% or less to avoid freezing up. Use a fan to circulate cool air better. Don't cook or take hot showers during the day. Avoid going in and out during day.
The heat can be tolerable in almost any rig. I have helped many others get their RV more comfortable for summer camping using these methods.