Who is Harry Cotton in the novel, Early Autumn?

Harry Cotton is a scrawny, potbellied man who seems to always have a cigarette in his hand and has "swooped" his hair up and over his head in an effort to hide the immense bald spot. Harry runs a car lot that is really a front for his illegal exploits. When Spenser discovers that Harry Cotton is involved, he notes that it means that Mel is deeply involved in criminal activities. Harry is crude, using profanity freely, and dresses like he has nothing though Spenser says that he's worth several million dollars. Cotton hires gunmen to kill Spenser after Spenser begins asking questions about his involvement with Mel, and the man hired shoots at Spenser while he's with Susan. Hawk's dedication for Susan means he is angry, and when Spenser refuses to kill Cotton, Hawk does it.