If you order off the website using the prices online, then you can use the codes for discount and free shipping (which is automatic over $250). If you use the reseller list, you get them cheaper if you hit the quantity discounts but you don't get to use the discount codes or get free shipping. And I'm assuming you email your order and they send you an invoice that way. Up to you to figure out which way will be cheaper. Amy will correct me and surely would answer this by email.