Buying a house in a rough area is just asking for trouble, what if someone breaks in and poops all over the walls then spends 3 months smoking meth in there, how much is it gonna cost to fix?
I'm being serious, the upkeep and risk of damage associated with it will likely be too high to turn a decent profit.
Other investors are buying a lot of the houses as high risk low cost investments - more gambling than anything, for the same reason millionaires have built entire towns which are completely uninhabited accross the world.