Never stock out, never over-order
The two numbers that matter
Economic order quantity (EOQ) is the order size that minimises the combined cost of ordering and holding stock. Reorder point is the stock level that should trigger a new order, accounting for lead time and a safety buffer for demand swings.
Raise the service level for critical inputs (like RM-204) to build a bigger safety stock; lower it for cheap, fast-moving items to free up cash.