Bare in mind that propane conversions of gasoline engines are loosing big on efficiency.
Propane has over 90% of gasoline BTU, yet the converted engines seem to use double amount of propane than original gasoline.
Than filling up propane takes long time after finding the station that will do it.
My Honda 3000EU did sit for over 2 years and started on 2nd pull on old gasoline. But I always run carburetor dry at the end of the season.
2.2 gallons of gasoline powered continuously my 15k AC for over 12 hr with way less noise that Build-in Generac.
That said, for times when I don't need AC, I am using $80 generator I bought at Harbor Freight.
2-cycle, but with small engine no noticeable smoke or noise and that thing will power my coffee-maker, my microwave oven and charge the batteries. Just not all at the same time.
