Trisha Sangus manages a large hotel. Recently, her hotel controller identified a problem in one of the hotel dining rooms. Essentially, Stevie, one of the evening cashiers, was voiding product sales after they had been rung up on the POS, and then removing an equal amount of money from the cash drawer so that the drawer balanced at the end of the shift. 

What procedures would you recommend to Trisha to prevent a further occurrence of this type of incident? Assume that a precheck/postcheck guest check system is in place.