Become a C21 Agent By joining the CENTURY 21 Tri-Cities Brokerage, you benefit from global brand awareness, powerful promotional tools and a world-class support team. CENTURY 21 Tri-Cities has the power to give you the edge to be... SMARTER, BOLDER, FASTER. Name Please enter your name. Email Please enter a valid email. Phone Please enter a valid phone number. Your Message Please enter a message. Send Message Sent! Message failed. Please try again.