The low profile oil filled electric heaters are best for us to use.. these are quiet in operation (Only go click) and do not give off burnt dust smell and above all have no open flame or visible heated cores.
We have two in our POPUP trailer, one sitting on a board in the back of our unused tent bed end and the other one sitting in hall way next to the POPUP door.
If more heat is needed to move around the trailer this size is perfect to sit one of the O2COOL type AC/DC/D-CELL 10-inch fans behind it. works great...
We usually run an extension cord into the trailer from the camp ground pedestal 20AMP connection just for the two electric heaters. Better to use the camp ground electric verses our POPUP propane when we can...
Roy Ken