Like Gordon Three, I dewinterize and use that time to check everything out. I usually get the propane tank filled, top off the gasoline, run the genset for an hour or so under load. I lubricate the power steps going into the coach, the slide, the locks on the exterior compartments, etc. I spray all the rubber around the doors and slides with silicon. I do a safety check on the propane system using soapy water and a brush. I check the hoses, belts, etc. I put back into the unit all the stuff I took out last fall to avoid freezing: bug spray, liquid soap, etc. I sanitize the entire water system, run up the frig on gas and electricity, check the solar outputs, flush out the hot water tank and so on.
In other words, I do an annual inspection and maintenance at the same time on just about everything I can think of doing. Takes all day.
Paul