Bare - minimum customer service may not be enough to earn the referral, though, so an agent has to make himself referable. If you have business cards, a nice website, and a brochure, you make it easier for clients to refer you to someone else. But to make yourself referable, you have to consistently deliver great service—showing up on time, calling back when you say you will, staying in touch once or twice a year with a phone call a birthday card (did we mention SendOutCards?)