You’ll only start saving money when you learn healthy money habits and let your future needs be more important than your current wants—aka when you make saving money a priority.

If you are dead set on a HELOC you will likely need the following for an investment property: An excellent credit score (720 or higher), A maximum 80% loan-to-value ratio, Healthy cash reserves on hand, Sufficient income from tenants, Additional features that make the property attractive, like whether it has long-term tenants (Source https://www.rocketmortgage.com...)

But, assuming I remain in relatively good health, I plan to continue self managing as many units as possible - I never expected to enjoy it, but I do!

. - its a shame that they don't teach how to live a financially healthy life in schools here in the "richest country in the world", but the internet, your community, and the local library are available to those who are willing to put in the time, set their ego aside, and learn. 

If an arborist told me they were healthy, I'd pass that information on to the neighbor.