The O-200 loves corn-free autogas, just get the STC. It's better than 100LL. If you get a tank on a small trailer, you can probably find a gas jobber in your area which will sell you 75 or 100 gallons straight from the pipe, before they add ethanol. I know one guy who bought a however-many-thousand-gallon tank trailer and buys autogas at wholesale pricing. Since it goes into his planes he doesn't pay road tax on it so he saves even more. Since it's a trailer, he doesn't have the buried-tank permit stuff to deal with.