Most articles about ERP open by telling you that you need one. This one will not. Plenty of companies run perfectly well on spreadsheets, and introducing a system would be money wasted. But there is a point past which Excel costs more than software — and it is worth knowing what that point looks like.
What an ERP is, without the acronym
An ERP (Enterprise Resource Planning) is a program where stock, documents, partners and money all live in one place. People also call it a business program, an invoicing program, a warehouse program or inventory accounting — in practice it is the same job seen from different angles.
The point is not the modules but one rule: data is entered once. A salesperson writes a quote, the quote becomes a proforma, then an invoice, then a delivery note — with no retyping. Stock levels change on their own. Nobody produces the report; it already exists.
Seven signs you have outgrown spreadsheets
- The same figure lives in three places. A price sits in a spreadsheet, in a quote and on the website — and differs in all three.
- Nobody knows stock without counting. "Do we have this in stock" ends with a walk to the warehouse.
- Invoices are written by hand. Someone retypes the same lines every month and occasionally gets a total wrong.
- You do not know who owes what. Open items are tracked from memory or in a notebook.
- A report takes two days. "How much of that product did we sell last quarter" is a project, not an answer.
- Everything depends on one person. When they go on holiday the company slows down, because only they know where things are.
- The file locks. Two people cannot work at once, so one waits.
One sign is not a reason for a project. When four or five pile up the maths changes — because each of them already costs someone's time.
When an ERP makes no sense
To be even-handed. If you sell a service with no stock, issue a handful of invoices a month and everything fits in one spreadsheet maintained by one person — stay on the spreadsheet. A system then adds data-entry duty with no benefit. The same holds if your range changes weekly and your way of working has not settled: settle the process first, digitise it second. Software that describes chaos only produces tidier chaos.
Off-the-shelf or custom
Off-the-shelf is cheaper up front and faster to launch. The price is that you adapt to it — if your workflow does not match what the vendor imagined, you will work around it. Billing is usually per user per month, so the cost grows as the company grows.
Custom costs more at the start and takes longer to a first version. In return it follows how you actually work, is paid for once, and has no per-user ceiling. It makes sense when something in the business is unusual — a specific document flow, non-standard measurement, or a need for the system to talk to your store or production.
Honest advice: if an off-the-shelf program covers eighty percent of your work, take the off-the-shelf program. Custom pays off when that eighty percent is never quite reached.
Cost and timeline
An honest estimate instead of a number pulled from the air: cost is driven by the number of modules, the volume of data to migrate, and how many exceptions your way of working contains. The most expensive part is never the programming — it is migrating existing data and getting people used to it.
That is why we do not start with the whole system. We take the part that hurts most — usually the warehouse or invoicing — build it, put it to work, and only then grow it. The company sees a benefit in weeks instead of waiting months for a big handover that usually slips.
What to ask before you sign
- Whose data is it and how is it exported? The answer must be "yours" and "at any time".
- What happens if we stop working together? The system should keep running.
- Who pays for changes after handover? Agree that up front, not when you need it.
- Does it connect to what we already use? Website, store, accounting.
- How long is the training? If the answer is longer than a day, the system is too complicated.
Conclusion
An ERP is not a status symbol; it is a tool against retyping. If your people spend a day copying figures from one place to another, that is already a cost — it just does not appear on an invoice. If they do not, stay on spreadsheets another year.
We build custom ERP and business software — from warehouse and invoicing to reporting, connected to an online store where it helps.
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