How To Buy Games From Gamefly -

You keep the disc you already have. GameFly will then mail you the original case , manual, and any unused DLC codes that came with the retail version.

If you are currently renting a game and want to own it, you can buy it without sending it back. how to buy games from gamefly

Check your rental queue under the "I Have Out" section. If the game is eligible, a "KEEP" button will appear with a discounted purchase price. You keep the disc you already have