A controller is in communication with a plurality of vendors that are servicing customers, as well as with a plurality of “subsidizing” vendors seeking access to those customers. The controller receives from a first vendor an indication of one or more items that a customer is to purchase. In response, the controller transmits, on behalf of a subsidizing vendor, an indication of an offer for a subsidy such as a reduction in the customer's purchase price. If the customer accepts the offer, the controller provides an amount of funds from the subsidizing vendor to the first vendor. The controller may also retain a portion of the amount as payment. The controller also facilitates a transaction between the customer and the subsidizing vendor. For example, the customer may be required to sign up for a service (e.g. credit card account service) that is provided by the subsidizing vendor. By having the controller manage such a system by acting between subsidizing vendors and vendors that are servicing customers, a vendor need only communicate with the controller, rather than a plurality of other vendors.