My friend and her adult son have lived in a SFH together for about 20 years. 

We have adult kids.

Thanks Sarah, I don’t see much house hacking going on in Essex or Dundalk in terms of listings on Zillow or FB so my concern would be finding professional adult roommates that want to house share in that area. i’ve been following a lot of the midterm rental groups in Facebook and the consensus is that contracts have decreased significantly and hospitals are using more local labor pools.

It's a sad state but most of the adult population does not do it.   

For example, I mention that every adult must pay a $30 application fee, pass my credit/criminal background, make a combined income of 3x the rent, and whether or not the property accepts pets.

You only screen adults.

Verify if there are additional adults or other violations.

Single adult + 2 kids2.

Communicate expectations upfront—because once they start double-parking or treating the place like a frat house, it’s game over.Cameras, Cameras EverywhereYou’d think adults wouldn’t steal each other’s food, right?

For example, I mention that every adult must pay a $30 application fee, pass my credit/criminal background, make a combined income of 3x the rent, and whether or not the property accepts pets.