This is a good question, with a simple answer:
First, you can e-mail us, contact us on LiveChat, or via phone, approving the additional shipping costs, and then we take care of the rest. Although we alert customers that, especially in today’s climate of massive gas prices, it costs us more to ship many packages, we will never charge you more than our actual cost of shipping. But when it’s more than a few dollars, we feel the need to alert the customer first, just to be sure you approve to head off any potential conflicts.
Secondly, if you want to “PRE-APPROVE” additional shipping costs for any orders, you can tell us that as well via e-mails, LiveChat, or phone. Your account will then be notated, and any future orders will not have any delays.