According to one embodiment, the present invention relates to a method and a system for implementing a card product or access mechanism with multiple relationships with an issuing entity (e.g., bank, etc.) where each relationship may be defined by one or more sets of rules that are customized for a particular customer. A computer implemented method and system for implementing a mechanism with multiple customized relationships may involve identifying one or more customized rules for an access mechanism associated with a customer; establishing a plurality of accounts for the customer wherein the plurality of accounts comprise different accounts with different account characteristics; and invoking one of the plurality of accounts for a transaction through the access mechanism, based at least in part on the one or more customized rules; wherein the plurality of accounts share at least one funding account.