Ones nearby of almost identical location & build (2 story) are going for $305k fully updated flooring and appliances.Friends condo has the original carpet, pet stains, original paint, appliances and cabinetry.Has new AC.We don't have a ton of money to buy it. 

If, instead, they are each on a separate, but otherwise identical Agreement, which specifies which individual bedroom they are renting, and what areas are "common" and accessible to others, then it would be up to you to give written Notice of Violation or a Non-Renewal Notice. 

All units are identical (2/1 with 800sf).

My numbers look pretty much identical to yours.

I would not rely on bank statements solely, as I have seen cases where the money was in the account one day, and gone the next due to gambling problems or identity theft issues.

Maybe their identity is extremely tied to what they do and less about who they are as a person. 

Bunch of thieves, dogs, and drug attics running around.

Rational people would tell the seller they are identical.

The Fair Housing Act - which applies to private landlords too - makes 'it is illegal to discriminate in housing on the basis of a person's race, color, national origin, religion, sex (incuding gender identity and sexual orientation), familial status, or disability." 

And when thieves brake in multiple times while your trying to rehab it ( see another BP post of a nice lady experiencing that) and let m know when you have to buy security systems so your houses don't get trashed..