I'm not certain this is responsive, but the new BSA Examination manual makes pretty specific suggestions regarding check sales:
Banks selling monetary instruments should have appropriate policies, procedures, and processes in place to mitigate risk. Policies should define:
• Acceptable and unacceptable monetary instrument transactions (e.g., noncustomer transactions, monetary instruments with blank payees, unsigned monetary instruments, identification requirements for structured transactions or the purchase of multiple sequentially numbered monetary instruments for the same payee).
• Procedures for reviewing for unusual or suspicious activity, including elevating concerns to management.
• Criteria for closing relationships or refusing to do business with noncustomers who have consistently or egregiously been involved in suspicious activity.
If I was going to the trouble to reduce all of the above to writing, I would also address the issue of verifying available funds and perhaps instructing the employee to draw the transaction to the attention of a supervisor if the amount of the check exceeds the average balance in the account.
In this world you must be oh so smart or oh so pleasant. Well, for years I was smart. I recommend pleasant.