Detroit numbers - what's missing?

[Mitch Monmouth]

I find many listings in Detroit Metro suburbs that appear to have a 30% cash-on-cash rental value - e.g. $40K in a decent neighborhood with $1100/mo rental value.

I'm sure some of these require work that would reduce that, but it still seems an astronomically high return. Any investor would probably be happy to buy such properties outright, provided the vacancy rates are low and the neighborhood isn't being abandoned, which at least for these listings is true.

Am I missing something? As we all know - if it seems too good...