I have several generators on the farm. The portable is 6kw will do essentials in my parents house (well, oil boiler, freezer, fridge and lights). Then I have 2 25kw PTO driven they work good older one is 20 years old works everytime. The big one I had to build a building around it. It’s 100kw 400 amp, power is 454 ci propane its hooked up to a automatic Asco transfer switch. I bought it about 5 years ago it was a cell tower trade in only had 150 hours on it. I think I paid about 5K for it fortunatly I have hardly used it I think it might suck some propane if I ever had to use it for an extended period. I know one of the mechanics where I bought it and they just got a bunch of trade in units about 1/2 that size and they want around 5k for them. They can be set up for propane or NG.