Minimum number of products before customer can check out

Hello everybody,

I’m busy with a new webshop, where it is intended that customers can only check out if they have 8 products in the shopping cart. It doesn’t matter if they put 8 pieces of one product in the shoppingcart or 8 different products. As long as there is a minimum of 8 products in the cart.

Second option (optional) is that customers only can check out if the number of products always per 8 is (8, 16, 24 etc.).

Does anyone know how I can make this work?
I couldn’t find any answer on this forum or google whatsoever.

Kind regards,

Vasco

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