The report makes a big deal about the neighborhood and local economy in addition to the property itself.

It seems you are the only person who understood the question wanting to know what a seller makes (not even sure how or why you think that).As a typical part of the DD process it is not uncommon to ask for property/entity tax returns.

Outside of wholesaling, I'd like to explore BRRR, Fix-n-Flips, and eventually Multifamily properties. 

If they've owned the property for 15yrs, probably a better chance of owner fatigue than someone only having it for 2 yrs.

I asked if they would consider seller financing on the property and they said, “yes”.

I'm looking at getting into the world of property management via a franchise.

I would say that a great thing any flipper can do is develop their own off-market properties.

When I closed on my first duplex in Harrisburg, Pennsylvania in August 2017, "the 2% Rule" was the gold standard for determining whether a property would cash flow.  

The key is to create an amazing property, in a great location, then manage and market it better than the sub-par property managers in the area. 

Leveraging creative financing methods like hard money loans, private lending, or partnering with investors can also help you secure deals when traditional financing is delayed or limited.