you can rent a tank at any o2 supply company. the tanks are cheap the problem comes when you add on a regulator. and a needle valve and tubing and all the extras you need to use one in a closed system. most companies i have been to will give you a tank when you buy everything else you need there. most have the exchange program just like the tanks for your grill......and the regulator and the trimmings run from 100-150 depending on the brand you get and quality of it.