I think the main thing would be access to the books to make sure of the expenses.

., shifts in pricing, demand-supply changes).Analyze local or regional real estate data.Identify key economic indicators impacting the housing market.Stay ahead of demographic changes or migration trends.Do you have any go-to platforms, datasets, books, or even strategies that have been especially valuable?

I recommend reading his books and then reading Thomas J Anderson who gives an opposing side about the use of debt appropriately.  

We have our Guide Book on the counter in the kitchen.People like to have something to look through, plus other guests leave flyers from places where they ate etc. with notes like, "Great food" etc. written on them. 

Read Dave Ramsey's book and i believe that will help you follow a system for getting out of debt and living below your means.

If there are any books, podcasts, or other resources that you’ve found invaluable, I’d love to hear your recommendations.And finally, if you could go back to when you were buying your first property, what’s the one piece of advice you wish someone had given you?

Totally worth it to cover any gaps.For managing it all, a Property Management System (PMS) could save you a ton of time by syncing calendars, automating messaging, and handling bookings.

When I looked into it, I saw that the STR she paid for was managed by Vacasa, yet the "owner" was answering requests from guests for bookings and taking money. 

I understand equity and cash-flow are related, but what I mean is that I don't need the cash flow right now as much as I'd like to build a strong portfolio that can cash flow even more later on.I've owned a single-family rental for 4 years, but on mulitple fronts I felt like I've done a poor job self-managing it, so this Fall I picked up the Turners' book on managing rentals and that's what led me here to Bigger Pockets online.

They charge 15% reservation fee for a complete management or $150 monthly if you do place bookings and they do coordinate maintenance, inventory, cleanings, front desk, admin stuff, and etc.