You should have just given the money to the housekeeper. Than you would, presumably, have been less likely to renege to her face. Even more fun, make two sets

You should have just given the money to the housekeeper. Than you would, presumably, have been less likely to renege to her face. Even more fun, make two sets of envelopes, one set of $10 bills and one set of $100 bills. The house keeper always gets an envelope, but your weight determines which one. That way, she's not too disappointed when you succeed, and when you fail, you've at least helped out somebody you like.