Complicated Flat Rates via Shipping Classes

Hi,

I was wondering if anyone could offer suggestions on how to implement this. It’s turning out to be more complicated than I initially thought.

There are two shipping classes. I need to apply the following to each:

Class 1: $6 flat rate for up 3 items, +1.00 for each additional
Class 2: $15 flat rate for 2 items, +1.00 for each additional.

My initial thought for class 1:
Cost per item is $1, minimum handling fee $6. But then I realized that there isn’t a way to designate that the $6 minimum applies to 3 items, and to start adding the $1 for the 4th item.

Any suggestions?

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