In October last year, during the artist's month long unofficial residency in New York, a street vendor set up a stall in Central Park selling what appeared to be reproduction Banksy prints.
He didn't have too many takers, attracting just three buyers throughout the day, and he soon packed up never to return.
The following day video footage of the stall appeared on Banksy's own website, along with the message: "Yesterday I set up a stall in the park selling 100% authentic original signed Banksy canvases. For $60 each."
Passers-by had missed the chance to pick up artworks worth thousands of dollars, but three lucky customers had unwittingly bought themselves the biggest bargains imaginable.
Now one of those customers is set to cash in on her good luck by offering her artworks at auction.
"The Central Park stall was one of Banksy's greatest coups during 'Better Out Than In', his 31 day unofficial residency in New York City, where he attempted to unveil a new work every day during October 2013," said Gareth Williams, Head of Contemporary Art at Bonhams.
"The fact that his paintings were original and were being offered at a tiny fraction of their true retail value raises real questions about the perception of worth and the nature of art as commodity within the marketplace, something that the artist must be acutely aware of."
Whether you call it performance art or a prank, Banksy's New York market stall has made a healthy profit for the trio of unsuspecting art collectors.
The two works heading to auction at Bonhams - 'Kids on Guns' and 'Winnie the Pooh' - are each valued at around £50,000 ($84,870). Not a bad return on $60, considering the woman who bought them for her children even managed to negotiate a 50% discount from the stall holder!
The two canvases will feature in the Bonhams Contemporary Art sale in London on July 2.
If you fancy adding to your art collection, or even starting one, take a look at the great items on offer in our online Art and Photography store.
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