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You might consider one that runs on propane since you already have propane available. No stinky, messy gasoline to worry about.
I've had a Honda EU 2000 for about 12 years now. Ran our cabin off it for years and now parell it with another to run the ac on my trailer. Guessing into the thousands for hours and still runs great. Had to clean out the jets once but extremely easy to get at the carb on these Hondas. Not the cheapest but very reliable and they hold their value.