I have owned a few hundred section 8 homes.. and you can take some serious ware and tear with those.. the adult children living at home ???

They are grown adults, right? 

I have a duplex with 3 beds 1 bath per side. 4 adults, 4 youth and a infant and water runs over $100 per month. more when they don't hear the toilet running and forget to call me to fix it.

I'm not sure how I should be thinking about renting a SFR out of state though.The neighborhood is one of the most popular neighborhoods for college students and young adults.

I am attracting stable families vs. young adults with roommates.

If it is more adults then you can limit parking if that is an issue.You may have some local laws about occupancy like number of unrelated occupants or minimum square feet to consider it a bedroom (you would call a room a den or office if it doesn't meet the minimum bedroom size). 

She claimed that her adult son had just gotten a job and he would be helping to pay the rent.

I do want to help the adults and at risk youth in the Inner City as well through Financial IQ Entertainment. 

I read somewhere that in Germany you open a savings account when you turn into an adult specifically for your down payment on a house.

An adult son and father will be living in the unit.