Heating the inside is fine, I doubt it will do any good for the pipes and lines under the floor or near a wall.
Best bet is to keep it inside and warm, but that will not help for long if you set it up outside in freezing weather.
Best to leave the tanks empty IMHO because there will be little to freeze.
2016 F350 6.7L LB CC Reese 28K 2014 Chaparral Lite 266sab
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