Fallout 3 GOTY help

So I already own Fallout 3, and have it installed and everything, but I was wondering if I could get the GOTY DLC for free. By this I mean, buy it from gamestop used, download the content to my playstation 3, and then return it. Because Gamestop's used game return policy is return it within 7 days for any reason for a full refund. Could I do this and then use my normal game disk and still get all of the extra content?

So I already own Fallout 3, and have it installed and everything, but I was wondering if I could get the GOTY DLC for free. By this I mean, buy it from gamestop used, download the content to my playstation 3, and then return it. Because Gamestop's used game return policy is return it within 7 days for any reason for a full refund. Could I do this and then use my normal game disk and still get all of the extra content?

Hissingace

Or you could rent it.

But yeah, concerning using the original Fallout 3 disk...