If you ask the owner of a corner shop in Kigali what they pay for inventory software, the answer is almost always the same: zero. They pull out a 60-page exercise book from under the counter, flip to today's page, and tap the column of numbers — proof that the system already works. We wanted to test that claim with a stopwatch.
The setup: one shop, one week, one observer
We chose a busy general shop in Nyabugogo that turns over roughly 700,000 FRW per day. Two cashiers, one notebook for sales, a second for stock-in, and a third (smaller) one for amadeni — customer credit. Three notebooks, three handwriting styles, one source of truth in the owner's head.
For six days we sat on a stool by the till and timed everything: the duration of each sale, the time to write a credit entry, the back-and-forth when a customer disputed an amount, and the nightly count.
What we measured
The numbers themselves were less surprising than how the owner reacted when we read them out loud. He shrugged at the 41 minutes. He winced at the Sunday three-hour reconciliation. And when we mentioned the 8.4% of items with no matching purchase line, he stopped smiling.
“The notebook is free the way walking to work is free. It costs you everywhere except the wallet.”
Three hidden costs nobody talks about
Most software pitches talk about features. We want to talk about what the notebook actually costs you, in francs and in trust.
- Time tax. 41 minutes a day, six days a week is roughly 17 hours a month. At a modest 1,200 FRW/hour that is 20,400 FRW gone — more than the Shop plan costs.
- Dispute tax. One real dispute per week. Whether the customer wins or the shop wins, the relationship loses. People talk, and customers walk to the next shop.
- Decision tax. You cannot answer 'which product made me the most money last week?' so you stock by feeling. The feeling is usually wrong, and the dead stock on the bottom shelf is the proof.
Every sale is logged in under 5 seconds. Amadeni is its own ledger with balances and due dates. The 'most profitable product, last 7 days' report is on the dashboard, by default. We didn't add these features because they were trendy. We added them because the notebook is failing in exactly those three places.
What we are NOT saying
We're not saying the notebook is stupid. It works. It scales to about 60 transactions a day, two cashiers and one location. Past that, the costs above start to compound.
We're also not saying software fixes culture. If the owner doesn't look at the numbers, no app will save them. But for the shopkeeper who actually does check at the end of every day, replacing the notebook with software is one of the highest-leverage decisions they can make.
If you only do one thing this week
Pick three products you sell every single day. Open a free Iwange account, add those three items, and run every sale through it for one week alongside the notebook. At the end of the week, compare. We have never had a shop owner go back to the notebook after that test.
The notebook is not free. It costs you time, trust and ten thousand small decisions a year. The good news is the alternative costs less than a phone bill — and your cashier will be running it on day one.
Reported and written by the Iwange team in Kigali. We do not publish individual bylines — what gets printed here was observed at a counter and checked twice before it ran.