I have used the Mr Buddy single canister propane heater for years from my tent camping days to my present OFF-ROAD POPUP camping days. This is my BACK-UP heat source. I can get around 6 hours of heat with the lowest setting. I can also get almost a full cup of water that comes off of it haha... I set mine in raised edge tray. Fills the whole bottom up with water.
The Tents as well as my Tent POPUP trailer is probably the only place I would even think of using these type of heaters. They will deplete the oxygen inside the tent as well as emit dangerous propane fumes. It is a must do situation of having a vent immediately over the top of the heater when being used. Sort of goes against of having a heater if you have to have an open window or ceiling fan area which is where my Mr Buddy is close to in my POPUP. I crack the ceiling fan about two inches.
If I was permanently mounting something like this I would most definitely go with the vented CAT 5 type propane heaters.
Consider these install photos from google seach. Pretty net installs.

Roy Ken