Propane here is about $1.50 / gallon so I am spoiled with the cheap cost. Dang, right now it is cheaper to run the propane furnace in the house than to buy firewood. We have 2, hundred gallon tanks that are free as long as we use the supplier for filling. If I remember right propane in a room temperature tank is about 170 psi, either that or the liquid is -170 F, can't remember. you might want to see if your welding supply house does bulk filling, since some folks use it in their cutting torches.