And this is CRE, so it's cutthroat, it's no one's problem but your own if you lose an earnest money deposit. 

Others will collect first, last, and a smaller deposit.

So the total amount that should be paid will be rent for remaining days in month + security depositORrent for remaining days in month + next month + deposit - I don't know when would this situation arise.

I'll reach out to the lawyer in the meantime, but I suspect if they refuse to pay it, it'll have to come out of their security deposits when they move out?

I've seen cases where the LP backed out of the deal at the last minute, not only leaving the operator at the closing table without the capital, but causing the sponsor to lose their earnest money deposit. 

At a bare minimum, I would require a written lease agreement and a standard security deposit equal to an entire month of rent.

If a buyer is coming down with a high-down payment and quickly making a large deposit into escrow fighting tooth and nail about proof of funds may be a red herring.Credibility is also a factor here.

Which is why there is more investment in real estate and bank deposits  in the “western world” (which includes.

Ideally, you'll want to see average 90% occupancy across the board, otherwise you'll be relegated to regional bank and credit union lenders that require (i) recourse, (ii) deposit requirements at close, (iii) slightly higher rates, (iv) lower amortization, and (v) less interest only [if cash flow is a priority for you]. 

Yes, you have a deposit, but it may not be enough.2.