I have one of those Mr. Heater that goes on top of a propane tank. Mines a single burner but you can get them in double and triple. Heats my garage in about 30 minutes, then you have to turn it off for a while. They are cheap and so is a propane tank. Oh yea, did I mention that they are portable. you can throw themin your trailer if you want to, just crack a window couple of inches.
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