Associated with my business I have three:
112 KW Taylor brand cummins diesel auto-start
25 KW Winpower PTO driven. Just about any tractor will carry it and run it.
6.5 KW Honda electric start, gasoline, EU series will run sensitive electrical stuff w/o harm. Honda makes outstanding/reliable small engines. Start it once a month, run the gas out of the carb each time. Extremely quiet. Sips gas. I think great for homeowner use as you described