TC modifier & 26 Modifier and leasing employees

I need clarification please. If we have a mobile imaging company come in and perform sonograms and they have one of their employees or they hire someone to read reports for them and my office wants to bill globally, is this allowed? The contract that is being presented reads that we lease equipment and personnel for the day. Or, should we just pay the company a flat fee for their time, we bill the TC component and the radiologist bills for the PC component?