This is the fourth and final column in a series based on a recorded discussion with George Collins, who died in October at age 85.George Collins handled many law firm dissolutions over the six decades he practiced law. He talked about the two issues that come up in almost every firm breakup: Who keeps the main phone number and who keeps the office space.“A law firm will have a phone number that is of value,” he said. “Both sides will want it. It depends on the type of practice. I was once partners with a …