As the OP is in South Carolina where the winter weather is about like mine here in Georgia...(or maybe better)
I like to keep the trailer ready to camp. Every now and then we get a freezing snap for a few days. I blow the lines out with air after draining from the low points. I keep a space heater in the trailer to keep the interior about 40 F when it's freezing outside. Be sure to leave all the faucets open as they are usually what gets damaged, not the flexible lines.
This way, as soon as the freeze snap is past, I'm ready to go out again without having to flush the fresh system. This requires "active management" however, you have to pay attention to the weather to run the heater and you will need to blow out the lines again when you get back from a trip.
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2008 (or is it 2009?) Rockwood 8280SS - 2007 F-150
Lot's of mostly Kenwood radios