Additional Purchase Data

{
    "customerReferenceNumber": "string",
    "customsDutyAmount": 0,
    "discountAmount": 0,
    "salesTax": 0,
    "shippingAmount": 0,
    "taxExempt": true,
    "itemData": [
        {
            "amountExcludingSalesTax": 0,
            "commodityCode": "string",
            "costPerUnit": 0,
            "itemDescription": "string",
            "itemDiscountAmount": 0,
            "merchantProductCode": "string",
            "quantity": 0,
            "unitOfMeasure": "string"
        }
    ]
}