Identify vouchers when freight amount used and exceeds certain amount

Good day Community,

Does anyone know if there is a way to generate a notification or worklist entry when a Payables voucher includes a Freight amount (in Voucher Freight field, not PO related) over a certain limit.

Because our invoices are scanned, there is no way to confirm that freight is ok to pay at time of building voucher

Generally, if a freight charge is less than $50 it is processed using the voucher freight amount option

When freight exceeds $50, the user should confirm with business that the charge is ok. The approval should be attached to voucher via an attachment or comment