As Armin mentioned, you will definitely want to pay close attention to the crime maps and shot spotter maps.

I've already requested a meter spotter to come out.

Definitely use Colin's advice on using the crime spotter. 

Spotting SolutionsAMMONIA SOLUTION- Mix one tablespoon of clean household ammonia with one-half cup of water.BLEACH -Use hydrogen peroxide or sodium perborate (present in Snowy or Clorox II).DO NOT use chlorine bleach.DETERGENT SOLUTION -Mix one teaspoonful of a colorless, mild detergent or dishwashing liquid in a cup of lukewarm water.DRY-CLEANING SOLVENT -Volatile dry spotter or a commercial spotter such as Thoro, Carbona, Energize, K2R.

That's a blip on the radar screen compared with the almost 3,000 REO properties in Illinois last month, according to data from RealtyTrac.Still, even baby steps in the right direction can be considered positive, particularly since foreclosure trend spotters say more consumers are likely to lose their homes given the nation's 9.4 percent unemployment rate.Bank of America, the owner of Countrywide Financial, services one in five residential mortgages nationally.The bank's intention with the program is to remove talk about price from initial conversations between it and cities.

You just have to have the right Contractors and Designers and Deal-spotters on your team!

My feeling is a war zone may be defined by a street that has the shot spotter system in place. 

Here are 18 ways to market to sellers...1) Properties that are FSBO2) Properties that are FRBO3) Direct mail to listed houses4) Direct mail to absentee owners5) Contact agents to work with you6) Contact insurance companies to reach out to the clients that have non-owner occupied properties7) Go to REI meetings and network with other investors/agents8) Bandit signs9) Car wrap10) Web Scraper11) Pay a referral fee to owners and agents12) Look for properties that have weeds13) Contact the city for a list of houses that have had the water turned off in 30 days. 14) Divorce attorneys15) Contractors16) VA’s to call FSBO and FRBO ads. 17) Hire a Property Spotter ($10 hr and require 5 leads per hour. 18) Zbuyer.com

I also check neighborhoodscout and crime spotter.