I would like to know where this $750K number is coming from. Generally Banksy originals of this kind are priced closer to low five-figures, but if someone has inside knowledge here please share.
I collect street art as my hobby and Banksy originals are much, much higher than low 5 figures for an original. Usually it's that amount of money for a print edition run of 150/200.
That said it is a supply/demand game and these aren't as intricate or interesting as his other pieces.
They might be pieces collectors have seen before, but on the other hand they're crucial parts of a one off performance piece, and I'd bet that adds value for collectors.
This article puts the value at around 20K pounds: http://www.mirror.co.uk/news/weird-news/banksy-sells-origina...