If you're looking for the best possible deal, go to an auction of repossessed properties. You may well end up paying 50% or less of the open 'market' value.
The problem is that you'll almost certainly be buying a property that has been extensively "gutted" by the previous owners, or other unsavoury occupants, since the repossession, and you may not even be able to get a mortgage to buy the place!
Sounds daft I know, but a recent mortgage case of my own experience brings home the point. The applicant was recently divorced and wanted to buy a home of his own. His previous wife had possession of their old home under a "clean break" settlement and no children were involved. He had been with the same employer for most of his working life and was in a very stable job.