Get some coroplast sheeting -----big box hardware/sign shops etc.
It is like plastic cardboard and is used to enclose underbelly on trailers
Couple boxes of self tapping screws
Some insulation
And insulate/enclose your trailers underbelly.......while open run a extra heat duct (flex ducting) from furnace discharge plenum into underbelly area so warm air from furnace flows around tanks/valves
$70 for propane...
30LB cylinder is 7.4 gallons........propane in TX cost $10/gallon :H
Even at $3/gallon that is on $21 per 30lb cylinder.
At 32*F...
Set furnace for 55*F overnight
Use space heater day time and early evening....but furnace to keep tanks/valves warm
