While auditing a client, the CEO asks you to look carefully at the cash flow. You notice that cash flows have decreased every year. Upon learning of your findings, the CEO remarks, “I seem to bring in more customers every year, but the cash is not there.” You tell him that fraud may be occurring, and he asks you to investigate. You agree that the most likely place for a fraud to be occurring is cash collections.
Which investigative method(s) would be best for finding the fraud?