Helping an appreciative customer may be the most satisfying experience in retailing, but dealing with "problem" customers also has its rewards-if you know how to react. Respondents to a recent JCK retail panel survey told us about some of their most challenging customers. We share their stories here in the hope that readers will benefit from their experiences. The forgetful customer. Tim Branscomb, owner of Sierra West Jewelers in Orem, Utah, recalls a customer who came in to pick up a ring in which he had mounted some diamonds. She asked to see the stones under a loupe and expressed alarm when she spotted flaws, claiming the diamonds were not the ones she'd picked. Branscomb showed the woman the original sale card with her signature next to the diamonds' specs. That jogged her memory. "Oh, now I remember," she said. "What do I owe you?" Branscomb believes in an ounce of prevention.