This is making my mortgage payment go from $2,293 to $3,308 per month. 

Also, I believe I saw somewhere that the mortgage won't count against the original owners DTI after a period of time if they show someone else is paying the mortgage.

Even better, I might be able to snag it well under market value since it's an estate sale that's been sitting on the market for nearly 200 days.Here’s the challenge: while I could afford to purchase the property under market value, I’d be stretching my budget thin to cover the mortgage during the period I’d be remodeling the basement to make it rentable.

Cover around 65% of mortgage Lessons learned?

True, but (a) they were typically experienced investors, and (b) today's market includes record prices and high mortgage rates, which is a double whammy. 

At the end of the day, cash flow was similar because I now had mortgage payments. 

For the property I purchase, I’d like to keep my monthly mortgage payments at $2,000 or less.I prefer a turn-key property since this is my first rental, and I want to start generating monthly cash flow immediately without the delay of repairs or managing two mortgages.

If your rent ends up being comparable to your current mortgage, it might not give you the cash flow flexibility you’re hoping for.

If you do want to go this route, make sure that the underwriting of the investment property pays back both its mortgage and the monthly HELOC.

Mortgage rates and PMLs are 8-12% plus points right now so the deal has to be a low enough entry.