A 20lb bottle, typically used for gas bbq grills and such, takes 4.7 gallons max of propane, your cost 16.40 plus tax. Like Latricia said fill 5x and get one free! If you're tank takes at least 3 gallons, you will still get a check towards your free fill too. Exchange cages offer you one advantage. You can get a bottle when we are closed. But in exchange for that convenience, you will pay north of $21 for a tank only 3/4 full.
You have 2 options, both will run you under 20 bucks. You can do the pre filled refill. It will be around 15lbs or you can bring your own and they will refill it. That route is a dollar or so less AND you get 20lbs plus you will get a card for a free refill after 5 paid refills.
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