best way to run residential fridge on limited shore power?

Refrigeration running on propane uses very little. You may have to manually shut off the ac to the frig as most will run on ac if it is present. Simply turn off the ac breaker for the frig and it should automatically shift to propane. Save your ac for the air conditioning but if you have to run two units on high in a 26' coach I would have them checked.... but on the other hand I don't know just how hot it will be where you are camping. Good luck.

:C