ABC Company is a relatively small dry-cleaning operation that has a very steady level of business. Since the company hired a new employee, however, cash inflows have decreased and the amount of promotional coupon redemptions have increased dramatically. The owner of the company has been very impressed with this new employee, but has suspicions regarding her cashiering practices. When comparing cash sales to check and credit card sales, the owner noted that the coupon redemption rate was dramatically higher for cash sales. The owner does not want to wrongly accuse the employee if she is innocent, but does want to find out if fraud is occurring. The owner calls you as an expert on fraud and asks you to recommend a reliable way of gathering evidence that could determine if fraud is occurring. What are some possible investigative methods you could suggest?