Question:  Should we allow commercial deposit accounts to cash checks at the teller window rather than deposit them and get cash back?
 
Answer:  As a "best practice," I would recommend requiring checks to be deposited.  Then you want the "cash back" to be documented with a check for "cash" or a cash withdrawal slip.  Remember that cash back transactions that exceed $10,000 must be reported on CTRs.  No exception.
 
One of the more common types of employee fraud is diverting checks that should be deposited or getting cash back from the deposit.  Thus, it is important to have documentation that will show up in the statement to reflect the cash out.  Then it is the responsibility of the customers to review their statements.