A homeowner association is a corporation formed by a real estate developer for the purpose of marketing, managing, and selling of homes and lots in a residential subdivision. It grants the developer privileged voting rights in governing the association, while allowing the developer to exit financial and legal responsibility of the organization, typically by transferring ownership of the association to the homeowners after selling off a predetermined number of lots. It allows a civil municipality to increase its tax base, but without requiring it to provide equal services to all of its citizens. Membership in the homeowners association by a residential buyer is typically a condition of purchase; a buyer isn't given an option to reject it. Some homeowner associations hire and retain property management companies. The board of directors is responsible for the retention of these companies.