I have been using the 100 pound 30 gallon tanks for years for the gas logs in our houses. As I am getting older and the boys are not at home anymore to help me move them I am gradually as the tanks age out replacing them with smaller tanks that I can move myself and not need a trip to the chiropractor afterwards. The cost is the same per gallon, a few extra minutes to fill multiple small tanks over 1 large one but my back is all the better for it.
I looked into having the propane company put a tank and deliver, they charge about 1.40 more per gallon than it costs to fill at Tractor Supply, for that much difference I can haul myself.