That really is insanely cheap, you couldn't build them for that!
If anything, you've publicised (for the better) a great source of sites: Auctioneers catalogues, so many quality untapped sites.
Hopefully this will mean more people looking out for stuff like this.
Cheers for sharing!
I'm guessing they have attempted to get planning permission for change of use to residential and failed, hence the price.
I would LOVE to have a crack at converting one of them!