A well to do woman was about to paint her back porch when she heard her doorbell ring. She answered the door and there was a teenage boy standing before her, dressed in rags. "Ma'am" said one of the boys, "Is there anything I can do for you around the house that you could pay us for? I can mow your lawn, clean out your gutters--" "Well", she said. "I like to do things for myself, but I guess I can let you paint my porch." "Where's the porch, ma'am?" "It's in the back", she said. "I'll get right to it!", the boy said. Fifteen minutes later, there is another ring at the door. She opens the door and sees teenage boy again, this time his shabby clothes are covered in yellow paint. "I'm all done, Ma'am", the boy said. "Wow, that was fast", she said. "Here's your money". She handed the boy a twenty dollar bill. "Thanks, Ma'am!" he said. "But there's one thing I think you ought to know before I go", the boy said. "That back there ain't no porch. It's a Mercedes!"