Walk around the inside by the windows and check for rot. Leaks can happen anywhere, but windows are a good place to check.
HW tank could be a number of things. The element might be shorted out and that might be why the breaker is blowing. Best guess is the anode has not been replaced in a long time, so there is no telling if the element is shot or there is other tank damage.
It would be an excellent idea to check the electric brakes and bearings. Replace the tires if they are 3 years or older. It is easier to change them now then when you are on the road.
Replace the smoke, propane and CO detectors. If the detectors are original they are beyond their service life. New detectors chirp when the batteries fail or the detectors exceed their service life. Old detectors lack that feature.
Have the furnace checked. A cracked core could be lethal. Don't rely on the CO detector for a check.
While they are checking the furnace have them check the propane system integrity.
Check the roof for damage and repair as necessary.
Check the slideout system for operability and learn how to retract it should it fail.
