What's cheaper to have in your home, oil, gas, propane or pellets?

as far as cost per therm, natural gas most of the time wins with fuel oil coming in first sometimes. Pellets are out the roof, propane prices swing wildly sometimes. If you rent your propane tank, you can only buy from the renting company. Ferrel Gas is who I rented from and I was charged much more for my gas than they sold to customers who owned their own tank. I bought my tank and they tried to keep me as a customer by selling cheaper to me now that I owned the tank.. I told them to take a hike. So if natural gas is not available, propane is great if you own your own tank and shop around. Whatever you get make sure it is a 95% or better efficient furnace.