I'd advise dealing this user with cautious -

1. I sent a completely fresh code to him first, he claimed the code is "invalid". I tried the code after he claimed it's invalid, and it shows the code "has been redeemed".
2. I told him if he has problem redeeming the code, I can create an account and redeem the code for him, after that he can just take the account, and he agreed.
3. As there's a slight chance that the code is compromised before I redeemed it (very unlikely though), I informed the code supplier about the issue, and they kindly offered me a replacement.
4. After the account is created and code is redeemed, he refuse to pay for it, and started to find excuses that only wanted me to send him the activation code first.
5. As this is de javu like my previous trade (which I almost got scammed), I told him that I will send him others with code or gift (he wanted 3-4 CSGO) after he paid for the created account. But again, he refused and only wanted me to send him the activation code.
6. In the end, he did not want to pay for the created account (which he asked me to create), and I don't want to send another activation code first (as he already stole one, and it's unrecoverable), we did not finish the trade in the end.

7. My advise? Stay away from this user or insist using escrow if you want to trade with him. I trusted these users by sending the code/account first, and it didn't get me anything good.