Does anyone know if there is a retail gas cylinder bigger than 9kg (say about 18 or bigger) that a person can swap or get refilled instead of relying on delivery? Also, would it be cheaper to refill my own cylinders rather than get them delivered? A 45kg gas cylinder delivered costs $150. The reason I'm asking is because I've just got my gas bottle "maintenance bill" from Origin gas for $71 I have two standard 45kg gas cylinders supplied by Origin obviously for our gas cylinders and a few years ago Orgin sent out a letter saying they were introducing a yearly "maintenance fee" of $19.50 to help pay for wear and tear on the cylinders they provide. Well... A few years later and that "nominal fee" has turned into a BIG one. I asked my local gas delivery guy what maintenance typically goes into these bottles and he showed me his spray bottle filled with soapy water and said, "See this, we just squirt a little soapy water around the valves and that's about it!" Then he belly laughed like Santa Claus If filling my own cylinders was viable I'd be happy to go exchange them myself. Any ideas or advice welcome.