Google Drive Inventory Workflow Setup

I need a self-contained inventory workflow built entirely inside Google Workspace. Intake and withdrawal will be handled through Google Forms, and each form must generate its own QR code so that anyone on the floor can scan, submit, and instantly update stock levels. When a withdrawal is logged the script should subtract quantities from the master Google Sheets inventory; an intake should add them.

The master sheet lives at the warehouse and must stay current in real time, but I also need automatically generated views that break the same data down by job number and by subcontractor. Feel free to use ARRAYFORMULA, QUERY, Pivot Table links or similar—whatever keeps everything live without manual refresh.

Every form submission should capture three key pieces of information:
• item / material code
• job number it is being charged to
• subcontractor who pulled or delivered it

In addition, the intake form must allow a PDF or image upload (BOL, packing slip, etc.) to a dedicated Drive folder structure; the file should link back to the corresponding line in the sheet.

Automation details
• Google Apps Script, AppSheet, or Add-ons are fine so long as they run natively in my domain.
• On-hand quantities cannot dip below zero; alerts or blocks are required when a scan would produce a negative count.
• All code must be annotated so we can maintain it in-house later.

Deliverables
1. Google Form templates for intake and withdrawal, each with embedded QR code.
2. Google Sheets master inventory with live add/remove logic plus separate filtered views by job number and subcontractor.
3. Drive folder automation that stores uploaded shipping documents and links them back to the sheet.
4. Clear hand-off documentation and a brief walkthrough video or call.

If you have built a similar QR-based system in Google Workspace before, let me know; I’m ready to move quickly once I see the approach.