I'm going to take the weekend to digest all this wonderful info from you and the other posters here, and I'll post again on Monday.

I know that's a lot to digest and it may cost you a little up front, but it will save you tons on the back end, and hopefully establish a great relationship with a contractor you can continue to use.

The vacant address data does not include a list of addresses or properties: It is a tabulation of counts and vacant/occupancy status of addresses in census tracts"

This means nothing without context, I realize, but just another "eyes on the ground" report for anyone to digest.

Most places in Chicago, even on the north side, will fall into the appropriate census tract to he able to avoid income restrictions.

The home possible income limits are by census tract, and available here --> https://sf.freddiemac.com/work... 

I drill down to the census tract as part of my due diligence and know specifically where to buy depending on funding.Let me know if you have any more questions and would be glad to help as much as I can.

This also goes for condo developments, as I can also bear witness to.I currently live in a 1970s-era tract-built townhouse condo in a development that's falling apart. 

So prime farmland with an existing annual lease will fetch a higher valuation than, say, a recently cut-over timber tract with a poor soil class.

I'm responding now to strike a balance between the time it takes for me to digest your multiple dense posts along with their accompanying links and the need for speed mentioned in terms of the property owner itching to sell now.Thank you very much for your reply.