How can I set a maximum required amount for a group of products?

Hi,

I am not sure if you mean you want to set a maximum quantity per order or maximum order sum. There is only a slight change to set up each. I am assuming you mean the maximum quantity. Here are the options you need to configure in the plugin’s settings:

General > Amount limits > Maximum
General > Amount types > Quantity
Products > Per product Category > Enable

Then go to the category whose limit you want to set as 4 items and edit it. You will find a new option for maximum quantity, set it to 4.

Now a customer will only be able to order a maximum of 4 products from this category.