Worst case get a double security deposit, a higher rent/guest/occupany fee, and make the SSN holder the sole applicant and the other adult as a guest.  

Without significant apprection that could allow some extraction of value, the negative cash flow on some of these purchases at some point will go through most newbies reserves forcing a sale,   They are adults and made adult decisions and took adult risks.  

We say that 4 adults aren't allowed.

They made an adult decision and should be held accountable.

While your kids are too young to be employees, you could still set up investment or custodial accounts (like a UTMA or UGMA) and fund them with some of your after-tax rental income, which can grow tax-free until they’re adults.

Discuss this with me like an adult.

Is it loud talking or fighting of adults?

If he is thoughtful and responsible probably not a problem but if you are trying to help a struggling adult launch beware.

You rent to responsible adults with good jobs.

I just read minutes on one condo O am looking at and saw a different unit had lost all amenities' access due to lewd and public adult acts.