First on the checklist is to lubricate everything:
1. Any moving metal parts like entry step hinges, key lock cylinders, door latches, hood hinges, basement door shock cylinders, slide-out gears/tracks, leveling jack cylinders, awning/topper hinges, etc. I use dry silicone lube that doesn't collect dust.
2. All rubber/plastic materials like slide-out seals, door/window seals, tire sidewalls, roof A/C covers, vent covers. I use Aero 303 for all rubber/plastic materials.
Second is to service the Generator:
1. Change engine oil, oil filter, air filter, fuel filter(s), spark plugs(optional). Generators like to run. Run often, without electrical load first, then with full load.
I bought a used 2005 Class A that sat a season and all hinges were dry. Did the service and everything works fine. Just finished 1,750 mile trip without problems.
Looking at your signature, you already know this stuff!!
Larry & Sue
2005 Georgie Boy Pursuit 3180DS, 31'5" Class A, 18K GVWR, 208", F53/V10, CHF, TST 507, FMCA, GoodSam