I need your help to find out how to make the orders only available in certain multiples. Here's an exampe of another shopify store using it: https://ibb.co/btMKPe
I have tried the MinMaxify and OrderLogic apps but they only allow one multiple at order level.
Does anyone know how this store has it?
Nick here from Shopify.
Great question. It could be worth reaching out to the website owner directly from the example you used to find out.
I did have a look for you in the app store also and found an app called Limits by Limitsify which might be able to do what you are looking for here. Other than MinMaxify and OrderLogic, it seems to be the closest to what you are looking for.
Alternatively, it could be custom and made by a Shopify Expert. It's quite difficult to tell without seeing the store itself, but if it is not from any of the apps you mentioned or the one I linked, it must be customized from the code in the back end.
All the best,