What are the overtime pay rules for salespeople and drivers?

Q: “Our salespeople work out of the company office making phone calls and also visit customers to make sales. Currently they are paid a weekly draw which is then deducted from their commission check, which is paid annually. Are we required to pay them hourly now? If so, is it still OK to deduct their weekly check totals from their commission check that is paid annually? Concerning drivers, if a driver drives both in-state and out-of-state, are we required to pay overtime?” – Em, Missouri