The relationship between an Account and Person in C2M/CC&B has its own attributes (primarily, for bill routing). These attributes are specifically applicable for the unique combination of the Person and Account. It would be ideal if the attributes associated with a Person and Account could be expandable in the same way that other levels of the V-model can be expanded (i.e. via Characteristics). If there was a CI_ACCT_PER_CHAR table or something equivalent, additional fields could be added to the relationship of the Person and Account. This would be helpful for including more information about how a customer wants to receive their bill or corresponded outside of the base fields as business requirements dictate. For example, a flag that indicates the customer wants to receive an envelope with their bill to send back their payment.