You can buy some portable electric heat / A/C units for about $600 for high power, less for lower power. They have an exhaust tube that you can run out a door or window, plugging the rest of the opening with blankets etc. I am installing an exhaust port (like a dryer vent) in our 78 Argosy to allow using one all the time, we live in Texas where our problem is heat. This unit will supplement our standard roof A/C unit, and have the dual advantage of being able to remove it and use it on my boat if I want to. They are about 12,000 BTU as I recall, but you could run it safely all the time if you wanted to, and sell them when you are done. They also are on wheels for moving around and are only about a 15 x 16 inch footprint.
I would just be very leary about the kerosene blower. Even if it turned out to be safe, seems it could leave a long term odor, which would be a shame on a re-done interior.