Blue Rhino propane tanks, 3/4 full

We have four used blue rhino propane cylinders / tanks. 3/4 full. Standard 15lb size. We just moved and found them all in the shed when we were moving out! Price is per tank. Pick up only. For $15, you get the tank and they are 3/4 full. It costs $20 to refill tanks and new they are $50+.