Ours is tri fuel. We heat with propane so it’s connected to the main propane tank. We only used it for 5 hours last summer so it’s still good to go. We bought one big enough to run the whole house. It’ll run the barn too but we do have to be careful with the load when we do that
Our daughter has a propane generator. It was there when they bought the house. It runs everything except the electric dryer.
However, they now run a business out of the house with a large walk in freezer. They sell raw dog food. So, they now are going to increase their generator size to a 20KHW so that it will power the freezer too in the event of a longer outage.
They offered us their current propane one but we would have to add a tank to fuel it. Our boiler burns heating oil. We also have a Harman pellet stove insert.