Thoughts to think on. . .
I own 7 properties totaling 14 units. 4 single family homes, a triplex, duplex, and a 5 unit apartment.
We started with a couple of flips, rolled some money into the rentals, rentals were bought using the BRRRR method, buy, repair/renovate, rent, refinance, repeat.
Find a house with obvious update needs that you can handle or you can pay someone a reasonable amount to handle. Fix them up and take them from a D property to a C+ or B level property (fix the holes in the walls, remove old carpet, refinish wood floors, update bathroom/kitchen, etc).
We have used HELOCs for this with the intent/knowledge that we are buying a $100,000 house for $85,000, with a plan to put $15,000 of materials into it and our own labor, and knowledge and plan to have it appraise for $150,000 to $160,000 when we are done. Once we have completed the home we have it appraised as part of a refinance and we pay off the HELOC with the loan. In this manner our house is only "exposed" to the market for 3 to 6 months during the renovation process. We typically aim to have no more than 70% leverage on the property when finished.
This method has allowed us to start building a portfolio of real estate for late in life, it also give us the ability to trade up in the future with 1032 exchanges.
I don't love a heloc used at your age, but short term while you're still working isn't as big of deal as it is if it is a primary component of the financing.
Also look at self-directed Roth IRAs you could potentially purchase a house within the IRA. Not sure on your local but near me you can still find some fixer upper 2bd/1ba homes below 75k that you could dip your toes on