A computer-implemented method for facilitating a payment transaction wherein a cardholder purchases an item from a merchant on behalf of a buyer is provided. The method includes receiving proposal data from a buyer computing device including at least one of an identification of an item proposed for purchase, a particular merchant, and a merchant purchase price. The method includes receiving a selection message from the buyer computing device indicating a selected cardholder chosen to purchase the item on behalf of a buyer using a merchant payment card associated with the particular merchant. The method includes reserving at least the merchant purchase price and a cardholder processing fee associated with the merchant payment card in a buyer account. The method includes transferring funds from the buyer account to a selected cardholder account, the funds determined at least in part by the merchant purchase price and the cardholder processing fee.