Cheating costs! For men, they are often required to purchase gifts for their new loves. Finding a place to commit adultery often includes paying for hotels. Other common purchases include lingerie, alcohol, and other entertainment related expenses. If you start seeing strange purchases or unexplained purchases it might be a sign that something is awry. Also, once a person starts to shop at a particular retailer on a regular basis, they will start to receive coupons in the mail from that store. Watch out for coupons for expensive chocolates, alcohol, sexy clothing, lingerie, and jewelry stores. Note – most women aren’t the primary gift givers in a relationship. This may not be as applicable for women – although you should beware if unexplained gifts start appearing around the home.