We rent helium tanks for $19.95 per day. This is in addition to the cost of the helium of $.20 per pound used. Please let us know what size and quantity of balloons you are filling so we can get a good estimate of what you will need. We gauge the tank on the way out and in and charge you for what you actually use. An 11″ balloon uses up to 4.2 pounds (or .5 cubic feet) of helium. A 12″ balloon uses 5.1 pounds (or .6 cubic feet). We also carry balloons, curling ribbon, balloon clips, and Hi-Float.