Shipping 1st class is limited to 13oz. If the product weight is under 13oz, the customer has the option to choose 1st class shipping. The problem lies in the product weight being too close to 13oz and when the order is packed into a box (which weighs over 3oz), I now have to pay to upgrade their shipping to priority. I know that the previous response to this question, several years ago, was that the product weight should include the weight of the packaging, but that only works if you pack one item per box. I sell stencils and other tiny items, so someone could order 300 items and still have it go 1st class. So I can't add the box weight to each one of those items or the shipping charge would come up as $800 for a package that should cost $4 to ship.
I know we can add a handling charge to each order, which I do, but with the nature of my products and customers, I cannot make that so high that it covers the cost of priority shipping. What would be ideal for me, is the ability to systematically add 4 ounces to the overall weight of each order, so that the 1st class shipping option disappears when the product weight plus box weight is not going to allow for 1st class shipping.
If anyone has found a work-around for this, I'd appreciate any tips. Thanks