Top commercial real estate brokers Doug Harmon and Adam Spies are working on a new contract with Cushman & Wakefield — negotiations that could impact how billions of dollars’ worth of real estate is traded. Harmon and Spies’ current contract with Cushman expires in October, five years after the brokers decamped from their longtime home, Eastdil Secured, in the fall of 2016. When the duo joined Cushman, they received a large signing bonus that’s been