I would like to insure with a mod that this trade is 100% secure and that if a scam occurs, the scammer will be banned and the money/ingame money will be reimbursed.
Read the donor deal rules. If the player does not have a rank, you will not be refunded. However it seems like you're the one buying them VIP, so I would make them pay first, and then buy them it. (Make sure you don't have them pay you until the thread has been made and you both have agreed to it)