You'll still be trying to get the place appraised and filling out papers and they'll have closed and started demo. 

It took about 8 weeks from demo day until completion. 

Your best bet is to hire someone to demo it on the spot or to haul it to the dump usually. 

Four weeks ago we dropped the dumpster to begin demo of the property and one of my sales agents stopped by to check out the project before work began.

Demo too!

There are REIA up the Ying Yang, Investors and lenders of all times.

You do not want to buy this property until this is resolved in case you are made to demo the unpermitted addition or pay fees to resolve the permitting.

@David Friedman I found this housing study that was done on ChicagoMain Site:http://www.housingstudies.org/Housing Plan Report: (lists income and demo by area)http://www.housingstudies.org/media/filer_public/2013/10/01/ihs_2013_overview_of_chicago_housing_market.pdf

Demo already begun and engineer and architect meet coming.

Our goal has always been to find a "forever" multi-unit in the city but the more I am thinking about it, the more I am thinking about the possibility of demoing our current 3 flat and building a multiunit, exactly how we want it, on the land.