Susan Green works in the purchasing department for Aftermarket Parts. During the past 12 years, she has been a very trusted employee and has sole responsibility for the company's purchasing function. She started working for the company at a salary of $35,000, and today she earns $65,000 a year. Fellow employees and friends have noticed a significant lifestyle change. Susan, a single mother of three minor children, is driving a new BMW, and last month purchased a 3,200 square foot lakefront residence in a gated community. Based on an anonymous tip, the CEO has asked you, the company's fraud examiner, to investigate the situation. What steps would you take to investigate the possibility of fraud?