[Mod edit - WSD, transactions for real world money is against TOS and can lead to permanent suspension from the forums and or Xbox live]
Love free codes 
Could use it 2
He didn’t say FREE, he said 40% off.
A free code is a free code weather it saves you money or not. If your getting a code from someone else, I class that as being free.
So I presume you are selling it at $24 then? I would buy at that price.
I would need some type of assurance and actual proof that the code exists. I just want to cover my bases because I don’t want any fishy internet transactions.
Anyone considering this kind of proposal should be aware of the possible consequences.