Just enter the Invoice number in space provided, enter the amount in the add to cart box, and proceed to checkout.
To calculate the "Add to Cart" amount to be entered, just enter the amount of money you owe with the period of the currency. Examples:
-If you owe $99.95, enter 99.95
-If you owe $500.00, enter 500.00
-If you owe $1145.95, enter 1145.95
To enter different Invoices, and have them detailed on your checkout, then enter 1 by 1 with their respective numbers and amount. This way you will have them detailed on your checkout page and your store receipt.