While this is a significant sum, trashing a unit by damaging the paint and flooring can easily result in expenses over $10k plus the lost rent, court and attorney costs. 

Multiple improvements done on this duplex in 2021, including new roof, gutters, flooring, drywall, electrical, appliances, and heating/cooling unit for the second floor.

I painted it, redid the floors, put on new doors and hardware, fixed all the existing issues (leaks in roof, toilets not working, sinks leaking, water damage on exterior and upgraded the panel to a 220V) What was the outcome?

Does anyone know if applying for 2 existing apartments on 2nd and  3rd floor with commercial space on ground floor in CMX4  zoning requires fire sprinkler system if no construction is needed? 

The main stack, drain lines in the basement floor, trap and the sewer line to the city main are the big ones.You can either knock these out as they become problems or bite the bullet and spend the money.

I now should be able to get it to 950ish as I got 950 for a 2 br top floor duplex in N Collinwood .

Value add was paint, flooring and a little gardening (as though that would add much value).  

Examples of SPACE not within the living area include a first-floor storefront with an attached residence; a rented apartment in a duplex; or a working farm with a farmhouse on the property.  

Super nice house with nice landscaping , hardwood floors in great condition, nearly move in ready with new furnace/hotwater/ central air.

Gulf front, 6th floor (so your views are over the tops of the palm trees) master bedroom with a king to sleep and an ensuite, two other queens, another bath and full kitchen.You might consider this a hybrid investment with vacation benefits.