I once read something from some real estate guru, who said he would rent out properties he owned, and live in rentals for himself
For some, it is about the location. They have the rentals they own in places that rent - but rent for themselves somewhere they want to live, but can't yet afford.
the nicer the neighborhood, the easier it is to find good, respectful, and paying, tenants.
For sure. At the moment, this isn't too much of an issue in Finland, though I suspect it will get that way in the future, as society crumbles further.