The signal-bearing medium of claim 1 whereby the selection of a particular service level agreement is made by a prospective service provider and wherein displaying the graphical representation of the selected particular service level agreement further comprises displaying an initial value of a service provider cost estimate, wherein the service provider cost estimate represents the cost to the prospective service provider of delivering service to a prospective service customer at the initial value of the at least one service variable and the initial value of the at least one service level attribute, wherein the operations further comprise:

receiving an updated value for the service provider cost estimate, wherein the updated value of the service provider cost estimate depends at least in part on the selected new value of the at least one service variable; and displaying the updated value for the service provider cost estimate.