There is a Mr. Heater catalytic heater DESIGNED for indoor use. It is yellow in color. I have one and use it in my home, when I don't feel like building a fire in the fireplace. Yeah, those 1 LB cylinders are getting expensive, but I have learned how to refill them myself, or look for them on sale. Propane is now $1.42 wholesale, still can't justify $4.50 for a 1 lb cylinder.
2003 GMC 2500HD 4X4 D/A Ext. Cab
Propane Powered Honda EU2000i
Lots of Hot Sauce!
Air # 283