If there is a can deposit on it as you find in many states, it can be as few 200. If you are just trying to sell it for the aluminum scrap value, then it takes about 25 lbs. to get $20. Cans weigh about 1/2 ounce a piece, so you would need about 800 cans.

5 cents a can in US or maybe 10 cents. 400 cans at 5 cents or 200 cans at 10 cents apiece

Yes. There are prices of many collecting agents.

http://www.ask.com/web?q=price%20for%20a...

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