Additionally, my experience with 203K's has not been all that kosher when you are looking to do more than 35k in renovations.

As John said, the appraisal not coming in high enough is the most common issue (not that it's very common, I don't want to scare you), but sometimes we can work it to your advantage if it's only off by a small percentage.  

In addition to what Trexie Recommended, BP has books on rentals and flips. 

To set the stage, I am currently growing my rental portfolio with the goal of getting 3 additional properties by the end of 2018.

My question to the community is what should I look for in terms of common problems.

Fairly common scam.One thing perhaps you can do as well is go when they are not there. 

Additional: I just called my HVAC contractor, they reminded me they were out last month and replaced a part.

In addition, my many years in the mortgage industry provided great real estate financial knowledge and access to capital.

It’s common to see some level of fees.  

I found a common theme by doing just that about generational or legacy wealth creation.