I even hired a private investigator to try to track them down, but no luck yet.

@Aaron Smith,This is definitely a pretty specific scenario, and I think the Appraisals issue (and finding a Lender that won't require them) will actually be the biggest deal breaker.However, I don't think I'd let that stop you from investigating a specific Lender's options, since even if the properties will appraise for well under their fair-market ARV, a Private Hard Money Lender might be willing to work with you.We've even seen deals in hot markets get funded at >100% of the Purchase Price or As Is Value, based on a higher ARV & knowledgeable Borrower that still inspire confidence in everyone seeing a healthy profit.Your biggest assets will be the free & clear properties, and the existing rental income.The biggest potential issue I could see would be if your existing debts will require too much to pay off with the new Blanket Portfolio Loan, that you end up with not much cash-in-hand after paying everything else off.It's an interesting question & scenario, so I'm happy to discuss further.

Questions for the Forum:1) Are there any major pitfalls I need to further investigate or be aware of?

To be honest, "investment strategy" is something I have no taken time to formulate, ( I've spent the last hour investigating exit and investment strategy on BP ).

A lot of them will be discovered when you conduct a more in depth investigation and during the due diligence process.I will provide a response to each of the 15 items you listed.  

One wrong move and your entire life comes crashing down.This sounds like a deal worth investigating, but not for you.

Since Jan 1, there have been 9 shooting homicides (pretty much all gang related), 15+ shootings (most appear to be gang related from initial investigations), and a bunch of car thefts (had a recent one month stretch that had 25 thefts).I'm sure this will affect the local market a but as potential buyers would see this and be turned off right?

While I am not a fan of entering into a deal then backing out and suing, some of your claims need investigating. 

Property was built in 2013, taxes as of 2014 and 2015 were $3,582     I will need to investigate how it will change Insurance costs?

You are right that it is best to investigate what programs exist.