It is reassuring that my initial thought to go with the 20 year when I would typically do a 30 is justified based on the lower down payment.

Everything depends on how you were structured initially!

Property has a lot of upside in terms of appreciation and with it needing mostly cosmetic work, we are able to BRRRR and pull out a decent amount of our initial investment (which came from private money, HELOC and personal).

In my experience since time is money, I always hire out this initial process and have professional who does this regularly conduct a thorough feasibility study to tell me what's the best route to get me the biggest bang on a particular lot, look at Density allowances, etc. 

The program is currently open for landlords to initiate an application for their tenants that are behind on rent due to COVID.

You can also set the deal up as a sandwich lease wherein you lease the property initially rather than purchasing it, and you then sublet it to a tenant/buyer. 

Like @Nicolas Nuvan said having a good realtor is key for a number of reasons- beyond negotiating on your behalf and walking you through the buying process they can give you a realistic idea on rents in the area and usually can help you with drawing up leases (which I didn't do initially but that you definitely need to do if you want to build a portfolio). 

A lender just told me about a DCSR loan and I'm looking into the feasibility of that.Based on what I've been learning on BP and from the forums here, I was initially looking for a house hack in Nashville, but have begun thinking that a flip may be the best idea to start so that I can make money to invest into the next property.

Part of my initial plan would be the equity / bond markets to help preserve my capital, offset inflation and provide me with a yearly withdrawal rate that would pay for my lifestyle.I am also considering where I can go / learn / invest in to put some of this capital to use within the RE world.

If you make a big enough glass (renovations and market appreciation) you’ll have your initial 20% back to use over again.