An area of due diligence on unredeemed tax defaulted properties that is sometimes overlooked is environmental issues.

But if you alter the stairs you may be required to bring them up to current code (which in some old houses requires a larger footprint so the stairs aren't as steep).

I might be phrasing it incorrectly- Alliance Environmental did the tests that showed we had asbestos in the popcorn ceilings and they are a company who can provide remediation, but they are not the company who caused the problem.

Someone could buy on contract and run down business, create further potential environmental liabilities, fail to make payments, and the market could decline.

ATT and Comast have limited footprints in the area and can be worth checking into IF you are in their service area.

An uninsured worker that gets hurt on your property or a contractor digging up a gas line with a back hoe or disposing of toxic chemicals like paint or solvents into an environmentally sensitive area can result in a huge liability that can easily exceed the value of the property.

(they measured the footprint of the buildings, determined roof square feet and then multiplied x the "going rate" to arrive at a price. 

This means your buyer pool is limited to people that really want a tiny home and care about the environmental impact reduction their building process has.

There are smaller more mom and pop turnkey outfits who have done a few flips here and there and usually they have horrible marketing and digital footprint.

IMO the grocery-retail-apartments all in one footprint is a nice model for redevelopment in urban areas where currently it's difficult to locate a big box style store plus parking lot, etc..I know a lot of people gripe about gentrification, but it's great for the long term viability of a neighborhood.