Meaning of cash buyer only

I was enquiring about a flat for sale near Elephant and the agent told me it was for cash buyers only. I am now wondering what the reasons are for a bank to refuse a morgage on that property. I guess it may be because it is located in a 10 floor council building but could it be anything more sinister? How can I find out more about the potential problems in that block?

A quick Google found this... http://www.mortgagestrategy.co.uk/dear-delia/106100.article (sorry can't do link thingy). It's a bit dated (2005) but I believe, the info is still relevant.

Most mortgage providers will not lend on high rise council blocks, so they have probably said cash buyers only so as not to waste time. It is not unique to that block, it is pretty much universal policy. The only way you'd get a mortgage on high rise council is with a humongous deposit and relatively small loan.