naturally the big advantage to a tri fuel setup, NG/propane regulators with venturi on a gasoline carburetor, you can take advantage of the fuel available...

propane..easy to store,especiall long term.... does not gum up the fuel tank/carb...25# bottle last about the same at 5gal gasoline on the smaller generators

gasoline...more filling stations (in Florida most gasoline stations have back up generators to run the pumps...the highly efficient inverter generators claim about 9hrs per gallon on standby mode...and can be converted to tri fuel also

natural gas...if you already have service much less expensive.. an YouTube vid by LDS Prepper made the comparison that during Hurricane Ike in Houston, neighbors with comparative size generators for 2 weeks had $500 vs $17 fuel bills...