I know this sounds rather odd because the whole point of an inventory app is to automate inventory tracking. Hear me out..
We are a manufacturing company and we need to track raw materials. I know there are apps that support bundling multiple raw materials into a finished product but automating inventory tracking is next to impossible for us. Sometimes we'll use substitute products, more or fewer of a type of product, breakage replacement, etc. So we would like to continue to manually track it but find a solution interface than the spreadsheets we are using currently.
A Shopify app would be great because I love keeping everything within the Shopify ecosystem but I would consider a separate system too.
If you are using spreadsheets currently then you can automate those processes and sync data into Shopify. We operate a product management platform that connects with Shopify.
We work with clients to customise our system to suit their needs as everyone is different. It would just be a matter of mapping the products up from the finished bundled product to each material. Each material would then have substitute options that you can update manually. Apologies if I am over simplifying.
We would have to take a look at the spreadsheets first and discuss how your data flow works currently to see the easiest way to automate the process. In the end it depends on how simple or complex you would like it to be. If you would like to discuss further just shoot me an email at email@example.com
I just came across your post, and I think the problem you're mentioning is happening in other industries as well for other Shopify merchants.
It might be worth taking a look at this app? https://apps.shopify.com/ready-pantry
It was built for restaurants initially, but the main goal is to keep track of raw ingredient count and link a Shopify product to these raw ingredients, with insights on your costs, etc.
Let me know if it helps! In any case, there is a 28-day free trial so you can see if it's suited for you @Shawn17