Girl With Balloon, 2004. Courtesy of Pest Control Office, Banksy, London. One of Banksy's well-known pieces is called Sweep it Under the Carpet and was made in 2006 on a wall in London.

Among them a single Banksy birthday card with a £15,000-£25,000 estimate sold for £23,000 while two others each made £11,000 exceeding their £8,000-£10,000 estimates. A design to stand ...