Piggybacking here. Depending on your heating energy source you need to size your generator properly. I have natural gas heating so I need enough to power the furnace blower, 1 fridge, 1 freezer, and probably a couple lights. I live in the upper Midwest so I also have wood stove ready to fire up whenever and a good cache of firewood.

Finally, again, depending on your water source, you will need to factor that in (public works vs rural well). If you have public works and your house starts getting cold make sure you leave a couple faucets trickling. If you have a rural well you need to know how to drain your lines. It’s not hard but you don’t want to learn on the fly.

...and don't forget that you'll need enough extension cords to go with it.