Look for the field "Terms" and select

 Finally, click on Save.

Once you add the Payment Status column and search for the orders of the customer with Pre-payment or 1% Prepay payment terms, you will see an icon within the Payment Status column for each order. If the order was paid, you will see a green check mark. If the order has not been paid, you will see a red warning sign.

 For those cases where you void an invoice, the system will not display any icon because an invoice that was voided cannot be paid and will not be pending for payment.