CENTURY 21 Banner Realty is a full-service real estate brokerage firm located in Fremont, Calif. Founded in 1973, the company deals in buying and selling of commercial and residential properties. It is a part of Century 21 Real Estate, which is the franchisor of one of the world s largest residential real estate sales organizations. The parent company provides training, management, administrative and marketing support. It comprises of more than 8,300 independently owned and operated franchised broker offices in over 50 countries and territories worldwide. Century 21 Real Estate is a subsidiary of Realogy Corporation, which is a global provider of real estate and relocation services.