+111 on the sweatpants/jacket. Cheap poly pile sweats are remarkably useful when daytime temps are not cooperating.
IMO, plan on keeping a window or two cracked open and wearing more clothes. Ixnay on the bubble wrap--the windows are going to be a source of cold but with extra clothes on you'll be fine.
Bring a supply of blankets--or even better--sleeping bags unzipped. Some here believe the RV should stay a steady 72 degrees all night, while others prefer a cold RV (me, for example) and simply adding or subtracting blankets.
If there's room inside the RV for an ice chest, bring one. Lunch meats, salame, etc will keep cold for days. I use an ice chest for frozen pizzas, because I can't be far away from pizza and beer for very long.
As said, you'll be running the gennie daily so just budget for it. And have fun!