not going to lie, that's a bit hectic. if it work for you, that's great.
Here's a screen grab of what we're currently using.
It runs on our server, so only accessible at work or VPN.
It connects to a database Via API that stores all the data for the stock list, print pricing etc. all products are created in there. It's easier and economical than hard coding the products.
The "price calculator" does all the calculations. I've made it so you can input up to 3 different quantity amounts to compare pricing.
it's still work in progress but i like the way it's working.
The settings page is where i and enter the API key and table settings. so essentially i could set this up on another server with another DB and not need to hard code anything.