You’ll never see an ad for Bob Cochran’s business, and even if you hire him, you won’t see his work, either. With twenty years’ experience installing audiovisual equipment, Cochran can hide any wire or cable, whether from a Sony flat screen or Bang & Olufsen speakers. On top of his design chops, Cochran gets high marks for his prices: $100 to $125 an hour, depending on the size of the job, which ranges from setting up a DVD player to configuring an elaborate entertainment system that streams music to every room of your house. His business is built entirely on word of mouth, but he can’t take all the credit for his success. Many of his jobs, he says, involve remedying other companies’ botched cable and stereo installations.