Also, for moral compass type questions an in-person interview would be best so both the verbal and non-verbal communication can be observed.  

Be prepared to observe:* Demeanor, interpersonal skills, communication style.

I can see, clearly, you have seen some red flags and are leaning towards not renting them.Furthermore, I sense, per my observation of this thread, a bit of anxiousness in renting out the unit quickly.

But honestly if you are happy with an expert that works in courts and legislature rather than observes in the real world, I have no reason to argue with you.

Its presence may exist without the knowledge of the structure owner and may be concealed from the untrained observer.

No real estate agent is gonna put that wreck on the market for 300k when it's probably not worth the money she owes on it.I think you should either drop it and find something in better shape for a beginner to handle or bring in a real contractor to inspect the damage and give line by line estimates on the repair costs.I believe you will find you need over 100k in repairs and updating assuming your observations were correct and verifiable.I wouldn't offer her more than 80k for the property as is which would make it a short sale and need 4 to 6 months for the bank to approve it.

I've observed it since I began residing in this house 5 years ago after my retirement.

I always say the cheapest education is sometimes hiring it done the first time and observing and learning.

For Rehabbing I would stick to East Nashville, Madison, Hermitage, Goodlettsville, Spring Hill, MurfreesburoAreas to avoid for rehabbing would be, Antioch, Cane Ridge, La Vernge, North Nashville, Whites Creek, Joelton, Pegram.This is based on data I pulled from the MLS and my observation.

I really like that observation on "adequately responsive".