we're soon opening shop and gona sell beer boxes. Each box should consist of exactly 12 bottles. Is there any possibility (additional app, plugin, code, etc.) that customer couldn't do check out if he didn't get full box/boxes? I mean the number of ordered bottles should divide into 12.
On the other hand, we also have other things for which this condition wouldn't be mandatory.
That's a great question! I believe that this should be possible using some custom coding. That said, just to confirm that we're on the same page - would the quantity of items in the cart need to be divisible by 12 in order for the customer to check out? Would this just apply to this specific product, or would that be a site wide rule?
You could use a Product Options app to do this if not every product will need to be effected by the condition. You'd have a box product and 12 required fields for each bottle option.
We offer a Custom Product Options app:
We don't limit the amount of fields or field groups you can create.
You can also make fields required and use conditional logic to hide/show fields and add additional cost for options.
Below is a link to our example store where you can see this app in action:
As mentioned above, you could potentially use an app to have mandatory fields. However, this would require having the different options all available on one product, whereas it seems that you'd like to be able to have various products be able to be combined in groups of 12. Your best bet here will be to contact one of our Shopify Experts and have them custom code that for you. Hope that helps!