You know, I don't know what my parents paid for it back in 2004 (ish). 

One report I saw said that something like 80% of the ADUs built were to house parents/children of the homeowner and were not being rented out.

Set up an LLC in the property’s state for liability protection, and consider a parent LLC if needed.

They have close family in the area they invest, perhaps even living in the investment property itself like their child who is a college student and rents other rooms in the house to friends, or their sibling or parent.

Born and raised in NY to Portuguese parents.

With a natural in and use owner occupied housing, you could likely end up with 1-2 houses a year (each in a new city).The other option is when your baseball career is over, you will most likely end up back in your home town, so you could start the brrrr process there with maybe your parents checking in on the work the contractors and property managers are doing.Best of luck.

You end up with X homes fully paid for and some crazy cash flow to live out the remainder of your days, donate to charity, or whatever your heart desires.

These initiatives exist in both Italy and Spain but are not meant to compete with developed areas like the Costa del Sol.That said, it’s important to note that I know the Costa del Sol very well, as my parents are from the region.

I also currently live with my parents which helps a lot. 

Middle aged people have aging parents, and we can't learn from clowns.