Safest way to heat an old trailer in cold New England.?

My large home burned down .I cannot afford another house. I own an old 1966 Holly Park trailer that is impossible to live in in cold Winter months. The heating system is old, forced hot air by propane.gas. I am forced to live here now. I am terrified. I have some insurance money coming and want to know the SAFEST way to heat this trailer in frigid weather. I want to install a new heating system that will not blow up, catch fire, etc. The trailer only has 60 amp. fuse electricity.I want to make this place as safe as is humanly possible. Of course I could insulate (It is metal and these are near a lake and were intended as Summer homes.) and get all new windows but this is awfully expensive.and I would not recover this investment if I ever sell it. ( The trailers value is low because of its age). Did anyone ever hear of installing a sprinkler system in a trailer. ? I fear propane gas (explosion). Any good ideas out there will be most welcome. I do have smoke detectors and a co2 detector, I also had these in my house that burned. They were of no help when no one is home and the homes on the street are not close together. Happy holidays and bless and thank you for any help or ideas you could offer me, all are welcome and thank you.