Is there any way to automatically combine shipping/handling charges for a buyer's invoice who has purchasee multiple items from me? I offer discounted S&H to buyers who purchase more than one item from me. For example, I may charge $5.00 shipping handling and only $1.25 for each additional item purchased, but when I go to generate invoices it automatically doubles the original shipping charge instead of applying the discount. Is there any way around this?

Thanks!