We have one SFR (our previous home) and we do our own version of house hacking by renting our downstairs MIL suite to two of our adult children.

Tell them all adults have to apply before they are approved to move into the property, take their application, and find a reason to deny from your criteria.

You may also take a QuickBooks class from an adult school.

I'd let them know you'll not be renewing their lease, you are going to a limited pet / animal policy, 1 per unit, adult weight limit of 20 lbs. .. or better yet no pet policy.Until then they must provide proof of insurance that cover them for their dog and I'd check again with your agent and see what their thoughts are,, I bet your agent says, to get a remove this animal as soon as possible and then you'd have to give them a mutual lease termination to show compliance for your insurance company until they are gone. 

I’m an adult and don’t need their approval.  

If you have a web cam, that's great!

Homeownership for young adults has been declining for decades, to around 35%.

For me it was playing on adult rec. league sports teams.Its a good way to bond and networking just follows after the games.That's why Real estate is so great.  

@Atul MohlajeeI was an adult teacher before I was a landlord.

You are an adult.