Electric vehicles (EV) are seen as one promising technology which can provide flexibility to the demand side in the electricity market. One promising application might be a car park where an operator schedules the charging processes of EV. This paper outlines a conceptual framework to enhance this demand side flexibility of EV customers with incentives through diverse service designs. Thereby, the development of a business model takes both sides into account: the offset between cost and benefits for the operator as well as tariffs with attractive incentives for customers. We focus in the following on a car park and give a comprehensive outline on the design of services for different groups of EV customers.