Vacuum Cleaner Salesman – Level 3

A little old lady answered a knock on the door one day, only to be confronted by a well-dressed young man carrying a vacuum cleaner.
“Good morning,” said the young man. “If I could take a couple of minutes of your time, I would like to demonstrate the very latest in high-powered vacuum cleaners.”
“Go away!” said the old lady. “I haven’t got any money!” and she proceeded to close the door.
Quick as a flash, the young man put his foot in the door and pushed it wide open. “Please let me in!” he said, “And see my demonstration.” And with that, he emptied a bucket of horse manure onto her hallway carpet.
“If this vacuum cleaner does not remove all traces of this horse manure from your carpet, madam, I will personally eat the remainder.”
The old lady stepped back and said, “Well I hope you’ve got a damned good appetite, because they cut off my electricity this morning.”