Example; you buy 3 and I am able to charge for 1 shipping. The buyer pays for 1 shipping, I receive payment for 1 shipping, I am charged for 3 shippings.
Are you absolutely sure you are being overcharged? When buyers purchase multiple items the FVF on shipping is prorated across the items with a portion relative to the individual item value assigned to each item.
Let's use round numbers.....
Buyer purchase three items 1 x $5, 1 x $10, 1 x $20
Combined shipping of $10
FVF on shipping @ 10% = $1.00
In your account the $1 will be divided, 14 cents to the $5 item, 29 cents to the $10 item and 57 cents to the $20 item.
Of course it will only work this way if the buyer makes a single payment for all three items. If they make seperate payments and you refund the excess shipping then you will pay the full FVF on the non-discounted shipping amount.

"What else could I do? I had no trade so I became a peddler" - Lazarus Greenberg 1915
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