Thanks for getting back to @PluginHive and I, @NiallS .
It sounds like you want to weigh food products. I did some digging into our App Store and you can use an app called Unitpricer to help you with calculating the product cost by weight and quantity. This app works for Shopify POS and you can switch units at anytime, offer a volume discount and get a report for products with a “sell-by” date.
Other options you can consider are using product customizer apps. Here are some of my recommendations:
Infinite Options - You can set minimum and maximum values on numeric fields.
Infinite Product Options - This app allows your customers to edit options in their cart without needing to start their shopping process again.
You can find similar options from our App Store, here: Product Customization Apps.
When you want to contact the third-party developer for questions or assistance, you can find their information listed under the “Support” section of the specific app’s page.
You can also look into hiring a Shopify Expert to help you with this request. Shopify Experts specialize in coding custom features into your store and can help with a variety of different tasks to enhance your store. You can find our Experts Marketplace here for a list of Shopify Experts in your area.
I’m curious to see what the community has to suggest!