If these people are so willing to evict you, and now gave you back your two month's rent, find another place ASAP - and use that money for a deposit and start fresh.

He would have every right to withdraw his deposit on the grounds that your "description" of what it would look like doesn't match the actual outcome.

Great tenant, they occupy the space maybe three nights  week, have it professionally cleaned and the check comes direct deposit .  

Meaningful deposit relationship..

Just like if you deposited her check in your bank account on the 30th, but you have to wait a week for it to clear - that doesn't mean she paid a week late. 

You should look at the content of the current lease but I would have them sign a estoppel  to verify terms/deposits ect. 

If you rent out a 1-bedroom apartment to a student there's a single point of contact, one person's security deposit if there's damage, one person to evict if things go really wrong, etc.  

You have 30 days to return the deposit.

That'll leave it in their mind that they can say goodbye to the $800-ish deposit if they choose to smoke inside, plus get a bill.

I'm nitpicking at this point but you'll run into different laws about the amount you can take as a security deposit, if you can legally ask for first/last months rent and a security deposit, etc.