I have purchased 2 properties in my life made a ton  (to me)  in equity in my first home that got me interested but never moved forward because after moving to my next house lost a ton of equity after the crash.

However, I probably am in a different stage of life that you are. 

Wake up the neighbors.That low-life will be back and most likely take it out on your property. 

I would even look at the active rental listings and what others are asking for, the conditions, and look at the days on market.

I have no idea how to start to estimate the money needed to get this property in a salable or rentable condition.

Good locationCash flowPrudent debtAdd valueReservesGood recipe with any market conditions.

There are unethical individuals of all walks of life and professions.

I like maintaining one month rent (8.34%) for Vacancy and hope for 3%.  12% - 15% combined for CapEx and Repairs depending on the age, current condition, and type of property.It still may be a good Buy and Hold deal.  

My long-term goal is tens of millions in real property and hundreds of thousands a year in cash flow, so that money no longer an obstacle in life. 

Life changes, and some of these people's lives are really up in the air.