Laura Haggarty from KatyDidsCards says:
I guess what I'd like is to have a base handling fee for the first item, then an additional amount added for each item the customer purchases, just as it works now.
Then the postage by weight could be added on by the calculator.
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Hi Laura,
It sounds like you might benefit from setting both an item-level handling fee in your calculated profiles and a package fee under Package Preferences.
A package fee will be applied once per package, no matter the number of items in the package. That may serve as your base while the handling fee you add to your profile will increase according to the number of items in the package.
Learn more about setting up Package Preferences in this FAQ:
https://www.etsy.com/help/article/6167