Here in Ottawa I notice a proliferation of places that sell "swap" propane BBQ tanks. The idea is that you simply drop off your empty tank and take a full one in its place. A lot of places have these tanks including many gas stations. They are stored outside of course, typically in a locked cage. Cost to swap your tank at one of these places is about $27. Cost to fill your tank instead of swapping it is about $16. That's a 70% premium folks! Many people think that once they have a swap tank, they have no choice but to go and swap it when they need a fill up. But many places will refill swap tanks, as long as the date stamp on it indicates that it is less than 10 years old, same restriction as any other tank.
I'm a software developer, NOT a financial advisor. These are just my own opinions/rants/musings on certain financial topics and should not be taken in any way as actual financial advice.
I can be reached at jim dot somerville at gmail dot com.