Personally, I would not keep a rental that is not expected to cash flow. 

If you're already stretched thin and expecting to hit 15-20 properties by year-end, hiring by summer makes sense, specially if revenue can support it.

Big expense up front, additional expenses over the life of the lock, they can be too complicated for renters to figure out, and they don't solve all the problems a landlord may face.

Also just look online and steal some ideas...I used to Google Luxury Kitchens and then figure out how to do the same for less $$.You'll be fine with your experience.

Over this time I have acquired my contractor team and have vetted them through my job as a property manager, figured out my strategy(Off Market/Deep buying) and location.

At any rate, I saw someone trying to explain how the @... works yesterday and I tried, but I really couldn't figure it out.

You could have used that $8800 to possibly have partnered with someone locally that is already doing the subject to deals to figure it out first hand.

Focus will be your superpower - figure out which strategy you like best and double down on that! 

Without knowing all of your specifics, I'd say that it's only worth holding on to if you can reasonably expect to have some really good appreciation in the near future (like 5 yrs)....Or, in the case where it would run well as a vacation rental, you could switch the usage, maybe?

Well I think he was planning to pay it but it wasn't long overdue so he certainly wasn't expecting a lien to be placed on the house one day prior to sale.