Once they move out, I would take any unusually high water bills, repairs, cleaning, etc. out of their security deposit prior to refunding any remainder.

Can the owner leave some money in escrow after closing with a deadline to get the tenants out or forfeit the deposit? 

The tenants have to either mail a cashier's check or money order to my PO box, deposit cash in the account or do a transfer if they use the same bank. 

Set up a separate business checking account to deposit rent and pay bills.

They email you nice statements every month and direct deposit the funds.

Offer incentives for direct deposits or day early pay to an account allocated for rents only.

I am not sure this debate has occurred here on the boards.First let's understand what the definition of a security actually is:The term ‘‘security’’ means any note, stock, treasury stock, security future, security-based swap, bond, debenture, evidence of indebtedness, certificate of interest or participation in any profit-sharing agreement, collateral-trust certificate, preorganization certificate or subscription, transferable share, investment contract, voting-trust certificate, certificate of deposit for a security, fractional undivided interest in oil, gas, or other mineral rights, any put, call, straddle, option, or privilege on any security, certificate of deposit, or group or index of securities (including any interest therein or based on the value thereof), or any put, call, straddle, option, or privilege entered into on a national securities exchange relating to foreign currency, or, in general, any interest or instrument commonly known as a ‘‘security’’, or any certificate of interest or participation in, temporary or interim certificate for, receipt for, guarantee of, or warrant or right to subscribe to or purchase, any of the foregoing.So right there at the beginning of the definition we see "any note".

You can get in a decent sized project if you use your $50k as your deposit for a hard money loan.

@Eddie T.I'm interested in getting a line of credit in the manner you mentioned, but can't you get a higher percentage of your deposit returned on the credit line?

The landlord did not require us to pay a security deposit.