After graduating from college, you work hard for 15 years, saving money to buy your dream property. Finally, you spend all your savings to buy a 300-acre farm with a splendid house and pool. Happy, an old college friend, stops by. She is saving her money to make a down payment on a coffee shop in town. You let her have a nice room in your big house for a few months, until she has the funds to make her down payment.

But odd acquaintances stop by almost daily for short visits, and you realize that Happy is saving money from marijuana sales. You are unhappy with this, but out of loyalty you permit it to go on for a month. Why is that a big mistake?