It Started With a Normal Friday

James runs a general duka in Zimmerman, Nairobi. He has been at it since 2021 — basic stock: cooking oil, rice, flour, soap, soft drinks. Nothing fancy. His shop makes between KES 8,000 and KES 15,000 most days.

One Friday in March, he restocked. Bought two cartons of cooking oil, a 50 kg bag of rice, 10 cartons of soda, and assorted items. Total: KES 42,000. He had KES 55,000 in his M-Pesa after a good week. The remaining KES 13,000 was for change and daily float.

Then Saturday happened. And Sunday. And Monday.

Three Days That Nearly Killed the Business

Saturday was slow. KES 3,200 in sales.

Sunday was worse. KES 1,800.

Monday, he opened and realised he could not pay his supplier who was coming that afternoon for KES 25,000 he owed from two weeks ago. He had KES 4,700 in M-Pesa. The cooking oil and rice he bought on Friday were still sitting on the shelf.

"I sat there counting money I did not have," James says. "I called my brother and asked to borrow KES 20,000. He said no. I called a friend. He said end of month. I was stuck."

He ended up selling his phone — a Tecno Spark he had bought for KES 12,000 the previous year — to a phone dealer down the road for KES 4,500. He combined it with the KES 4,700 he had and the KES 1,200 his wife sent him, and paid the supplier KES 10,400 of the KES 25,000. The supplier left angry.

What Went Wrong? Three Things

1. Stocking without a cash reserve. James spent 76% of his available cash on restock. That left almost no cushion for a slow weekend. In a business where daily sales fluctuate, spending nearly all your cash on inventory is a bet that every day will be a good day.

2. No separation between business money and survival money. The KES 55,000 in M-Pesa was everything — next week's stock, his kids' school transport, his own lunch money, change for customers. When you mix it all in one account, you cannot tell if you are profitable or just surviving.

3. No plan for a bad weekend. Every duka owner knows some weekends are slow. But most do not prepare for it. James had no emergency fund, no credit line from suppliers, no backup plan. One slow weekend turned into a crisis.

How to Protect Yourself From the Same Situation

Rule 1: Never Spend More Than 60% of Your Cash on Restock

If you have KES 50,000, your restock budget is KES 30,000. The remaining KES 20,000 stays put. That is your buffer for slow days, emergencies, and the unexpected school fee demand that always comes on a Monday morning.

This sounds hard when a supplier offers a "good price today only." But that good price is only good if you survive the next week.

Rule 2: Open a Second M-Pesa for Business Only

You do not need a bank account for this — just a second Safaricom line (KES 100 for a new SIM). That number is strictly for business. All sales go there. Stock purchases come from there. If you need to pay school fees or buy personal items, you send yourself money from the business line to your personal line. This one habit gives you a clear picture of your business cash flow.

Rule 3: Track Your Best and Worst Days

Get a notebook. Every evening, write two numbers: today's sales and today's expenses. After one month, look at your best day and your worst day. The difference will shock you — and it will tell you exactly how much cash reserve you need to keep.

If your worst day is KES 1,800 and your best day is KES 16,000, you need at least enough reserve to cover three worst days in a row. That is KES 5,400 minimum before you think about spending on stock.

Rule 4: Build a Relationship With a Supplier Who Will Wait

James's supplier left angry because there was no relationship. A supplier who knows you and trusts you might give you a week. Find one supplier — even if they charge slightly more — who will let you pay after you sell. That relationship is worth more than a KES 50 discount per carton.

The Simple Test That Could Save You

Here is one question to ask yourself every time you restock: "If I sell nothing for the next three days, can I still pay my supplier and eat?"

If the answer is no, buy less stock.

It is that simple. Kenyan retailers lose inventory before they lose customers. The shelf full of goods you are proud of is also cash that is not in your pocket. Cash that is sitting on a shelf cannot pay a supplier, cannot pay school fees, and cannot handle an emergency.

James learned that lesson the hard way — by selling his phone to keep his shop open. Do not wait for your weekend to break you.