[jdhn]

You still can get a house for that much in Detroit, however you'll potentially be living in a dangerous neighborhood. Safe Detroit neighborhoods have actually soared in cost even if they aren't in the downtown area, believe it or not.

[walrus01]

If I were to do something like that for habitable, ready to move in house under $100k in some post-industrial economically depressed city, it sure wouldn't be Detroit with all the big city problems that come with that... Somewhere much smaller like Oswego, NY or Elmira, NY.

a somewhat randomly chosen example in 45 seconds of searching: https://www.zillow.com/homedetails/51-E-5th-St-Oswego-NY-131...