[QUOTE=Bigd9;2447045]I have a 1 gallon or 5 pound sized propane tank I used a lot for portable grills. However it has just pasted the 12 year life and needs to be re-certified. QUOTE]
Home Depot carries the Worrthington brand of empty propane tanks.
I have found that they tend to have the best prices on the tiny 1 gallon tanks. Their price ranges from $25-$60, depending on the time of the year. (probably classic demand/supply driven cost).
Mine is usually used with a portable campfire, and a Weber 200 grill.
The 1 gallon tank has been used with the motorhome's extend-a-stay, in a pinch! It sure looks funny, but it's better than having to pack up and leave!