A small store needs three things to stop running out of stock: one accurate stock count per product, a reorder point based on how fast each product sells and how long the supplier takes, and a purchase order log that shows what was ordered, when, and what has arrived.
The two costly mistakes
Small stores usually lose money on inventory in two ways: a best-selling product runs out and sales stop for days, or cash sits in products that don't move. Both come from the same cause: no simple system that shows what is in stock, what is selling and what is on the way.
I have handled inventory control, purchase order records and pricing reports for businesses, and today I manage an online store's catalog and suppliers. Before a store needs a full system such as Odoo, this setup is usually enough.
1. One accurate stock number per product
Decide where the true stock number lives: usually the store platform itself, since Shopify and WooCommerce both track inventory. Then make sure every movement updates it:
- Sales reduce stock automatically
- Returns that can be resold are added back
- Damaged items are removed with a note
- New deliveries are added only when counted, not when ordered
Do a physical count of the fast-moving products regularly and fix any differences.
2. Know how fast each product sells
From your sales history, calculate how many units of each product you sell per week on average. Group products into three simple classes:
- Fast movers: most of your sales, never allowed to run out
- Steady: sell regularly, reviewed each month
- Slow: sell rarely, reordered only on demand or discontinued
3. Set a reorder point for each product
The reorder point is the stock level at which you place a new order. A simple way to set it:
Reorder point = weekly sales × supplier lead time in weeks + a safety stock
The safety stock covers delays and unexpected demand; make it larger for fast movers and unreliable suppliers. When stock reaches this level, the product goes on the next purchase order.
4. Keep a purchase order log
A simple sheet with one row per order line:
- PO number and date
- Supplier
- Product and quantity ordered
- Agreed price
- Expected delivery date
- Quantity received and date
- Status: ordered, partly received, received, cancelled
This log answers the questions owners ask most: what did we order, from whom, at what price, and is it late?
5. Follow up with suppliers on a schedule
Each week, filter the log for orders past their expected date and contact the supplier. Write down the new date they give. Over time, the log shows which suppliers deliver on time, which is useful when negotiating or choosing a backup supplier.
6. Review slow stock every month
List products with stock but few sales. Options include bundling them with best sellers, a targeted offer, or not reordering. Decisions on discounts stay with the owner.
When to move to a full system
Consider an inventory or ERP system such as Odoo or Zoho Inventory when you manage several warehouses, many suppliers, or need inventory connected directly to accounting. Until then, a clean spreadsheet and disciplined updates do the job.
Summary
Keep one accurate stock number, know your sales speed, set reorder points, log every purchase order and follow suppliers weekly. That prevents most stock-outs and frees cash from slow products.
Inventory and purchasing is one of the services I offer. See my services.