A method on a server for managing sales activities and group buying offers for a plurality of users over a communications network is disclosed. The method includes receiving sales transaction data from the users, receiving recruit enrollment data from the users, processing the sales transaction data and the recruit enrollment data to generate aggregate data pertaining to sales, transmitting the aggregate data to the users, receiving a group buying offer, transmitting the group buying offer to the users, receiving acceptances of the group buying offer, calculating a number of acceptances of the group buying offer, effectuating a sale of the product or service of the group buying offer to each of the users who accepted the offer, if the number of acceptances of the group buying offer is greater than a minimum number, and attributing a particular sale to a recruiter, so as to award a commission.