I got the Rig over to the RV repair place and when they got to doing the work they found that
the brake problem wasn’t as terrible as it felt; seems that a pivot point for the brake near the engine was rusty and some WD40 and rust penetrator spray loosened up the device and it appears to be working. Although I am still leery of it working properly. My problem with the heater was in the thermostat control, the contacts were corroded, The water heater wouldn’t work on electric and it turns out the heating element is kaput and needs to be replaced, it is on order. The generator was not sounding right and it needed an oil change. The carburetor was adjusted the oil and filter changed and it runs smooth now able to power the AC without sounding like it is going to die. When I drove it home the brake pedal worked fine releasing the brakes as it should. Now to put fuel treatment into the fuel tank and run it through the generator and engine to clean the carburetor on the generator. A lot got done in just a few hours, sure makes a difference when you know what to do and have the right tools.