Trade Battlefield 3, Get Modern Warfare 3 For $1

Gamestop UK will allow you to buy Call of Duty: MW3 from them for £0.99, around $1.35USD, all you have to do is trade in your copy of Battlefield 3.

This is a pretty good deal if you are a CoD fan.

Simply purchase Battlefield 3 before midnight on October 27th and then purchase Modern Warfare 3 before midnight on November 7th. Gamestop will refund you for your purchase of Battlefield 3 except for the £0.99/$1.35.

You will need to send Battlefield 3 back to Gamestop before the 18th of November to be eligible.

That works out to be slightly over a week of playtime before sending it back for CoD:MW3.

Modern Warfare 3 will cost £41.97 at GameStop while Battlefield 3 costs £36.97.

Activision obviously has this accounted for in their marketing plans and the slightly higher price point.

If you are unsure of which of the latest multi-player shooters you intend to get, well, this could be a great way to try them both.

This is a new step in the war for players, a fairly dirty one too. Sure, this deal has Gamestops name attached to it, not Activisions, but you would expect they are involved.

Source: Quickjump/Eurogamer

So i need to buy BF3 until tomorrow night,
Can i buy MW3 on the 5th on November for example?
Second question: Where the hell should I go to give this game to Gamestop in my country?!
Supposing that I gave them BF3, are you sure i'll take back the money i gave to purchse BF3? (36,97€)
If yes, Where will I get them from?