I sell a lot of small items and when buyers decide to bid they obviously don't know if they will be successful and they often chose a shipping option which covers a number of items - eg $8.50 for 20 items. They are then successful on multiple items and ask to pay by direct credit on the combined shipping rate I have quoted on the listing. However I am paying fees on the shipping rate they selected which is $8.50 per item. So in some instances I am paying over a dollar to sell an item which is less than $2. Is there a way around this please?