I have read that if your initial intent was to rent the property and you end up selling, that would qualify for a 1031 exchange.

If you live in a Tenant-friendly state like Oregon, California, Maine, Vermont, or Hawaii, you should seriously consider investing in another state or finding another way to make money with real estate like flips or tax sales.

Notice the word intent.

I've been toying with the idea of getting into rentals as some more supplemental income, and although I've struggled with the math as far as justification, i believe the main reasons folks here by rentals (please correct if I'm wrong) are: Cashflow (although I've seen people do deals eg on Roofstock for only $100-200/mo) + appreciation (when sold) + taxesSo assuming I'm correct there, then the potential tax benefits are 30% of the reason to do rentals.

By trade, I am an Family Law Attorney; however, Real Estate is my main passion, so I made the switch about a year and half ago.  

I would also encourage you to do a Double Closing because having a property under contract, with no intent to purchase, and marketing the property is illegal in many states.

I bought my house in 2015, with the intent of one day turning it into an income property.

My main question was: When I'm looking at numbers (and say I'm targeting a MFU listed around $80k for instance), if I pay for the multi-family unit using a HELOC from my primary residence, do I load that number into my calculations as "cash to close?" 

He’s in tax foreclosure has till may 30th to pay $21,000 which he has no intentions on doing.

I also invest mainly in Des Moines off you’d ever like to meet up reach out.