You have not cited any testing procedure you have done such as checking breakers.
The GFCI suggestion is a good one. Usually GCFI protected outlets are used any place they can get wet, In my MH this includes the kitchen area, both bathrooms (one of which actually contains the GFCI) the External outlet and an outlet in the dining area near the floor (I have no clue, othes in much the same level are not GFCI)
IN addition you have a breaker panel or two or three or four in your coach
(1:Main power panel, optional generator if using generator, optional inverter if using inverter, and optional inverter sub panel if using inverter)
The last choice is bad wireing. Wires can break or come loose. Breakers can go bad. This level of testing requires test gear and some knowledge of how to use it