They've said I need to learn to be more responsible, and that I'm endangering their financial wellbeing.

I have been working on a post about insurance and it is very complicated.Proper is very expensive but it is very comprehensive.

Learn from red flags and screening processes going forward (if anything makes more sense in hindsight). 

Not too familiar with market dynamics in that area but would love to learn more.

All the gurus & mentors tell you that you can do real estate with no money or credit, except, of course, for the money you have to pay them to learn plenty you could easily find for free online or just thru the School of Hard Knocks. 

it’s evolving as we speak Lessons learned?

This can be a good niche but you will need to go deep to learn about it.

But from those conversations I have learned it is block by block. 

Learning from those who have navigated similar paths before you can be immensely beneficial as you embark on your investment journey.I happen to be a member of the NCREIA myself.

If you don't already own a home yourself, I always suggest house hacking as this gets some skin in the game, but also allows you to learn hands-on and offset your mortgage payments.