@Rich Weese , when I was in second grade, we moved into a home where the previous occupant had taken apart and presumably rebuilt a car engine in one of the bedrooms.

Baltimore has good and lower grade areas like other large cities. 

Don't pull permits, buy lower grade finishes, etc.

AttomData has a few more data sources than zillow and they licence their data for resale similar to landgrid ( I'm sure you can just get a regular consumer grade API from them as well).

On the other hand, if this is a basic rental, I can see the value in simply telling the contractor, "use builder grade products" and allowing the contractor to choose the material within a price range you set. 

Is there anyway to reverse engineer from a sold listing so you can work out the costs of construction (not including financing or selling/marketing the property) so you could essentially roughly know how much it'd costs to build a similar grade house per square foot?

Investment grade deals are found off market.

@Hassan DeWittYou'll need a neighborhood map to differentiate neighborhood grades what average rents are nearby based on room count. 

If you're looking at Cleveland you'll want to read The Ultimate Guide to Grading Cleveland Neighborhoods.

If you're looking to do some research on Cleveland neighborhoods you'll get a ton of value from The Ultimate Guide to Grading Cleveland Neighborhoods.