--- title: "An inventory system for a growing shop: when spreadsheets stop working, and what the first real system should do" description: "Spreadsheets work until you have two branches, two employees or a supplier asking what you need. The signs you need an inventory system, and what the first one must do." lang: en canonical: https://www.kerneltics.com/en/blog/inventory-system-for-a-growing-shop source: https://www.kerneltics.com/en/blog/inventory-system-for-a-growing-shop alternate_ar: https://www.kerneltics.com/blog/inventory-system-for-a-growing-shop type: article published: 2026-09-22T00:04:55.237Z updated: 2026-09-22T00:04:55.243Z author: "kerneltics" tags: ["مخزون", "Odoo", "متاجر", "تجزئة"] --- # An inventory system for a growing shop: when spreadsheets stop working, and what the first real system should do > Spreadsheets work until you have two branches, two employees or a supplier asking what you need. The signs you need an inventory system, and what the first one must do. Most shops in Saudi Arabia start with a spreadsheet, and that is right. It is free, everyone knows it, and in the beginning the stock is small and one person knows all of it by heart. The problem is that the moment the spreadsheet stops being enough does not announce itself. It arrives as scattered small problems: an order placed twice, a product that ran out with nobody noticing, a year-end count that did not match. Each gets fixed by hand, until the manual fixing becomes the whole job. This post is about how to know you have reached that moment, and what the first inventory system should actually do for you. ## The signs that the spreadsheet is done - **More than one person edits the same file.** The moment two employees receive goods or sell, the file has two versions, and each one is "right". - **More than one branch or warehouse.** The balance in Riyadh is not the balance in Qassim, and the spreadsheet knows only one. - **The count does not match.** If a gap between the file and the shelf has become normal, the file is no longer a source of truth. - **The supplier asks "what do you need?" and you have no answer.** Reordering becomes guesswork or memory. - **You sell online.** The store sells a product that is not there, or fails to sell one that is because someone forgot to update the file. - **E-invoicing.** Once the invoice has to come from a ZATCA-compliant system, the spreadsheet is out of the picture anyway. If two of these apply, you are ready. If four apply, you are late, and that is no disgrace; most people are here. ## What the first inventory system must do Not everything. The first system has specific jobs, and the rest comes later. ### 1. One correct balance per product in every location This is the foundation. Every receipt, every sale and every transfer between branches changes the balance automatically, with nobody typing into a file. When you ask "how many of these do we have?", one number comes back, and it is right. ### 2. Every stock movement has a record Who received, when, from whom, and at what cost. Who sold, to whom, in which branch. When a count shows a gap, you know where it happened instead of blaming everyone. ### 3. A reorder point Each product has a number: when the balance drops below it, the system alerts you or prepares a purchase order. This alone ends "it ran out and nobody noticed". ### 4. Barcodes Receiving, selling and counting with a scanner instead of typing. It cuts errors and speeds everything up, and any serious system supports it from day one. ### 5. Invoices and purchases connected A sale produces an e-invoicing-compliant invoice and reduces the balance; a purchase records the supplier invoice and increases it. A system where you enter the invoice once and the stock separately is not a system, it is a spreadsheet with a nicer face. ### 6. Simple reports you open on your phone What sells most, what is sitting, what is about to run out. Not a dashboard with fifty indicators; three or four numbers you open every morning. ## What you do not need at the start - **Manufacturing and assembly**, unless you actually manufacture. - **Automatic demand planning with forecasting.** It needs a year of clean data before it helps. - **Integration with every delivery platform from day one.** Start with the stock; integrations come after. - **Customised screens.** Let staff work on the standard layout for a month, then decide what deserves changing. Each of these adds cost and time, and delays the day you finally have a correct balance. ## Off the shelf or custom? For stock in a shop or a group of shops, the answer is almost always off the shelf, specifically [Odoo](https://www.kerneltics.com/odoo): its sales, purchasing, inventory and point-of-sale modules are mature, e-invoicing connects to it, and it grows with you into accounting and payroll when you need them. A custom system earns its place when your stock has a nature the standard modules do not cover. We saw this with auto parts, for example: alternative numbers for every part, compatibility with specific vehicles, and one supplier with ten names for the same product. On the [Zaiti project](https://www.kerneltics.com/works) we built that part as a custom module on top of Odoo, not a system from scratch. We explained the trade-off in [Odoo or a custom system](https://www.kerneltics.com/blog/odoo-vs-custom-system). ## How to move off the spreadsheet without stopping the business 1. **Clean the spreadsheet first.** Duplicate products, different names for the same item, lines you no longer sell. This is the most important week of the whole project. 2. **Decide the unit of measure and the barcode** for each product before it enters the system. 3. **Do a physical count** on a quiet day; that is your opening balance. Not what the file says. 4. **Start with one branch** or one warehouse for two weeks, then the rest. 5. **Keep the spreadsheet for a month**, for comparison only, not for editing. If the two match after a month, close the spreadsheet. ## How long, and how much? It depends on the number of products, the number of branches and how clean your data is today. The part that takes time is not the system; it is cleaning the data and the opening count. We fix the timeline and the price after a session where we look at your current spreadsheet, and we do not quote before that because the number would be wrong. ## The short version A spreadsheet stops being enough when there is more than one person, more than one location, or a supplier who wants an answer. The first inventory system must give you one correct balance, a movement log, a reorder point, barcodes and connected invoicing. The rest comes later. And the move succeeds on clean data and a physical count more than on the system itself. If you would like us to look at your spreadsheet and tell you exactly what you need, [book a free consultation](https://www.kerneltics.com/book).