I store outdoors. I add fuel stabilizer and run engine and generator for 15 min. Then I remove engine and house batteries and take home. Batts are then charged fully and kept off charger til Spring in the relatively warm garage (they are never where they can be in below freezing air). No Rv cover and after eight winters its fine (no mold). I keep the tires on wood to keep them off the ground. This year I started putting moth balls in milk jugs with holes hanging under the coach, sitting in he kichen sink, and under the hood where the starting battery would be (as a mice deterrent). So I obviously do not run the engine at all. I also think its a good idea to have ended the season by doing a fresh oil and filter change first and when running the engine to circulate the fuel stabilizer you will also be bathing the engine In fresh oil. Good to change generator oil and filter also.
