Their children (now in their late 40s) inherited the house, but they have not listed it on the market, and I heard that neither is willing to move into it from their current setup, so the property has been sitting vacant.

On most any day you could find people walking dogs, or children playing in the area.

I lived in a college town and student rentals did very well as did STRs for parents coming in to visit their children.  

We go above and beyond when it comes to protection.. starting with insurance coverage, sings in the listing and in the property that there is no guard on duty (as silly as that sounds), putting extra locking device high enough so youngsters can't reach, an alarm/beep system to alert them that door opens for those with small children (or elderly) so they cannot wander out in the backyard with no one noticing and risk drowning.

Providing relocation assistance to tenants, for example, if I want to sell the property or move back in - this can range from one month's rent to thousands of dollars (e.g tenant has a disability, minor children, elderly it will cost you more), depending on the city.

They have no ****ing idea.Your $500k salary likely has a 401k, health, vision, dental, etc.

and I gotta tell you it's really fun to get to see the impact of my legacy gifts while I'm still around to watch my children prosper.  

They are nearing retirement and have children in school.

I also recommend you do your own dental work.Which of these makes sense?

If we adopt this mentality, then all OB/GYN doctors should be female and have children.