"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 wedged his foot in the door and pushed it wide open. "Don't be too hasty" he said "not at least until you have seen my demonstration" and with that he emptied a bucket of horse manure onto her hall 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,
Spoiler:
