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Depends on how warm you want to get... Also remember there are venting issues with all heaters that use combustionable material as their heat source.
For serious deep winter cabin heating, I use a 20,000 btu radient heater, mounted to a common 20lb propane tank. It''s quiet, smoke and smell free, but requires a good supply of fresh air. I also use a houshold battery powered CO monitor to make sure the yard does not find me curled up on a bunk during spring commisioning.
You also have to be aware that such a heater is an ignition source for flamable fumes, so painting is a big no-no with one.
If your heating requirements are more modest, Coleman makes a tent rated 3,000 btu propane heater that runs on the small bottles you would use on a portable grill or a hand held torch. About $30 and runs for 3 -4 hours on a 1 lb tank.
Propane heat also gives off a lot of water vapor, so be aware of that if you are trying to dry things out.