Hi,
-If you set reorder level and quantity for respective item on item master form then Automatically create Material Request if item quantity falls below defined reorder level. https://manual.erpnext.com/contents/stock/item
For Item monitoring ,you can refer reports of Stock Balance ,Stock Ledger
in that you can see how much quantity Delivered and how much quantity still available in stock with valuation rate also.
Thank you for that reply. How about to monitor each performance of the three depots? The only initial solution i can think of is to create a new company for each of the depots. I don’t know if that would be the best solution because technically they are all still under one main company. What do you suggest?