@Jake Calle Based on personal experience and market knowledge, the first areas I would suggest looking into are the neighborhoods south of Gandy Boulevard in South Tampa, West Tampa, and, if you're open to wood-frame build houses in an up and coming / hot area, certain parts of The Heights (Tampa Heights & Seminole Heights). 

This may be a solid option for you if you are open to this route.

Keep the duplex, fix it up and rent it out, knowing that I'll never be able to sell it and the heirs could come along at some point and open an estate on the duplex3.

She is open to owner finacing but it has to be short term and she still owes on the property, so she would have to take a second on the property, and I do not know how much the current balance is on the loan. 

Is it a building violation to have such an open view to private property?

We are open, humble and personable.

Then I emailed the contract to title company to open new escrow and close the deal.

One has opened up close the Seattle area for $70k up from $50k in 2011 and it's a 3/2 1800sqft built in 1991 I've done the research and from what I've seen it's around what most are selling in the area.

For example, suppose I had an appraisal conducted with a proposed floor plan of a building I'm renovating after a fire with no offices built (not a shell but just a finished, open floor plan) and the cap rate in that appraisal was 9.0%.

It’s about 6pm when he calls and says lights are on in the house and when I knocked someone opened the door and said they rented it.