In a method of purchasing online, a client device of a customer communicates a purchase selection which is received by a vendor computer system. The vendor computer system, in response, communicates a cost of the purchase selection and fund confirmation address to the client device. The client device communicating a payment authorization for the cost that is received by a fund guardian. The fund guardian confirms the availability of sufficient funds to pay the cost. The vendor computer system communicates a fund confirmation address which is received by the fund guardian. When sufficient funds are available to pay the cost, the fund guardian communicates a fund confirmation to the fund confirmation address.