Chiming back in here.....about draining the generator's carburetor. Today's fuel is so very clean, and with cleaning additives & 10% ethanol. Today's fuel evaporated inside a carb does not leave residue or varnish behind. Granted our garage is heated, but I cannot imagine that temperatures would change how the fuel evaporates and what it leaves behind in a carburetor.
For long term storage, I don't drain or run anything out of my lawn equipment engines, my PC generator, PC, Corvettes, Solstices, whatever. My lawn equipment, I just set them down and let them be....and much of my equipment is near 30 years old now. My vehicles, I store them with a full tank of gas and I never add a stabilizer. Fuel anti-freeze is a real joke now that the fuel we all buy has 10% ethanol in it. Why add a small bottle of extra when you have gallons of the stuff in your tank already?
I personally like the idea of driving the motor home once in a while if being stored outdoors, just to keep the brake rotors from rusting badly. I think brake rotor rust and rodent damage will be your most serious threats during outdoor winter storage.
Running your PC and generator engine during storage does no harm as long as you run them long enough.