My friend's parents bought (one of) their retirement homes in phoenix at the lowest dip in prices. I believe they got a $300k+ house for $150k or lower.
I remember living in the quad cities (Davenport, IA) the neighborhood I lived in was nice but it had a lot of deviants that ran around randomly breaking into houses (girl next door got robbed). Anytime you get a reputation for that it easily knocks off a good $10-15k from the typical price. i.e. good vs. bad neighborhood, in this case a bipolar neighborhood