Employee Victoria Livesey walks past Banksy's “Kate Moss 2005” on display at Bonhams on March 23, 2012 in London, England. The painting, estimated at GBP 30,000 – 50,000, USD 48,000 – 79,000 and 35,000 – 59,000 euros forms part of the Urban Art Sale, which takes place at Bonhams on March 29, 2012. (Photo by Peter Macdiarmid/Getty Images)

Employee Leonora Oldfield looks at Banksy's (L-R) “Love is in the Air”, “Leopard and Barcode” and “Bomb Hugger” at Bonhams auctioneers on March 23, 2012 in London, England. (Photo by Peter Macdiarmid/Getty Images)

An employee holds Banksy's “Girl and Balloon” which was painted on an Ikea frame at Bonhams auctioneers on March 23, 2012 in London, England. The painting, estimated at GBP 15,000 – 25,000, USD 24,000 – 40,000 and 18,000 – 29,000 euros, forms part of the Urban Art Sale, which takes place at Bonhams on March 29, 2012. (Photo by Peter Macdiarmid/Getty Images)

Employee Victoria Livesey looks at Pure Evil's “Infinite Neon Bunny” at Bonhams auctioneers on March 23, 2012 in London, England. The neon installation, estimated GBP 1,500 – 2,000, USD 2,400 – 3,200 and 1,800 – 2,400 euros forms part of the Urban Art Sale, which takes place at Bonhams on March 29, 2012. (Photo by Peter Macdiarmid/Getty Images)

Employee Victoria Livesey looks at “Zephyr” by Andrew Witten at Bonhams auctioneers on March 23, 2012 in London, England. The painting, estimated at GBP 6,000 – 8,000, USD 9,500 – 13,000 and 7,100 – 9,400 euros forms part of the Urban Art Sale, which takes place at Bonhams on March 29, 2012. (Photo by Peter Macdiarmid/Getty Images)