For the record, I spent most of my life in Minnesota, so I don't personally think its THAT cold in Tennessee, haha. Just worried about the RV...
I bought a couple of caged light bulbs. The only ones they had at the hardware store said they were rated for 75 watt bulbs. I've got one in the bay with the water pump and filter, and the other is in the bay with the city water hookups and black/grey tank valves. I also leave the storage bay lights on.
I left a small Dixie cup of water in one of the bay's over night to check for freezing. So far so good. Tonight it's supposed to get down below 20 degrees. A little colder than last night, but I'll keep the furnace cranked and see how it goes.