Product Quantity Per Parcel implementation

I’m setting up a website that sells coffee beans online and the client has a Courier Guy account. I’ve installed the plugin and everything seems to be working. But during testing, we saw that as you increase the quantity of the products in your cart, the shipping costs increases per product. So for example, you would purchase 1kg of coffee and the shipping would be R60. And then for 2kg the shipping would be R120. But up to, let’s say 5kg, depending on the shipping method, only one shipping fee should apply, according to the rates sheet we’ve received.

I’ve contacted tech support and they said I should specify ‘Product Quantity Per Parcel’. I have to specify the amount of packages per parcel. And in theory, this works. Up until a certain amount of packages, only one fee will apply. But how do we implement this practically? It would make sense to calculate the weight of the total products and then work out the shipping, but apparently we need to physically count the amount of packages that can fit into the Courier Guy parcel. Also, not all the available shipping methods will have the same rate. So one method will allow for 5 packages and another will allow for only 2 packages.

What is the best way to set up this plugin for shipping on an online store? Are we over complicating this? Any feedback would be greatly appreciated.

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