Resources used in education on DSCR:https://www.biggerpockets.com/blog/dscr-loans-what-are-theyhttps://www.biggerpockets.com/blog/dscr-loans-terms-to-knowhttps://www.biggerpockets.com/blog/brrrr-loans-what-are-the-options-and-how-do-dscr-loans-stack-uphttps://www.biggerpockets.com/blog/eight-questions-and-answers-to-dcsr-loans?

Fix-and-flip projects can yield quick returns but require experience, while house hacking with FHA or conventional loans is a great way to get started.

I've seen where people add so many loan extensions with optional payment.Say 1k gives you a 1 or 2 year extension and this can be done 4 or so times.This agreement could be changed so many ways to make it work.You could offer a higher interest rate after 7 years to extend to 15 years.

Assuming you have a loan on that property you co-own, you'll need to "extract" that equity somehow and convert it to cash to be able to use it on another property. 

VA loan.  

My wife and I both have decent paying jobs, but after paying rent, vehicles, student loans, etc, there’s not much left over for saving, let alone 20% down.

The price was 500k and we used a DSCR loan for the purchase. 

You will need down payment money, You will need cash reserves Money, you'll need closing costs money, and you will need to get a bank loan.

Last month, my wife and I purchased a fantastic duplex in Madison, WI, for $400,000 using an FHA loan.

I disagree, I had a time when my name and the name on the insurance didn't match and the lender was all over it, regardless of the on-time payments.Your best bet is to refi into a commercial loan that allows the LLC (if you've already purchased the property), or close directly with a commercial loan / DSCR loan.