Just Looking, Rohnert Park, CA
If you view the town as intersected by Hwy 101 and Hwy 12 created four quardrants, avoid the SE quarter almost entirely (lots of newly developed units in there with some nice pockets, but area as a whole has issues). Avoid the SW corner near the 101 (further west is fine). The upper half of the NW corner is fine, and most of the NE corner is fine above 4th Street.
That's just a general guide. If you find something specific you're interested in, look for stats for that area.