The verdict in three sentences
In 2026, an internal web application replacing a stack of shared Excel files costs EUR 20,000 to 55,000 in Amsterdam, delivered in 10 to 16 weeks. The real issue isn't the development price but the hidden cost of Excel: entry errors, duplicates, no audit trail, hours lost consolidating. A business app with roles, permissions and dashboards turns a fragile file into a reliable, auditable tool.
What makes up a business app budget
The scope of internal management varies, but the cost structure stays stable: data modeling, entry interfaces, roles/permissions, dashboards and exports.
| Module | 2026 range (EUR) | What it replaces |
|---|---|---|
| Data model & entry | 6,000 – 14,000 | Scattered Excel tabs |
| Roles, permissions, auth | 3,000 – 7,000 | Open-access files |
| Dashboards & KPIs | 4,000 – 10,000 | Manual pivot tables |
| Accounting exports & reports | 2,500 – 6,000 | Copy-paste to the firm |
| History & audit trail | 2,000 – 5,000 | "file_v3_final" versions |
| Deployment & training | 2,500 – 6,000 | — |
| Total | 20,000 – 55,000 | One reliable tool |
Typical timeline is 10 to 16 weeks. A reduced scope (1 process, 3-4 roles) fits the low end; multi-department management with an approval workflow climbs to the high end.
Excel vs business app: the real comparison
Excel looks free, but its real cost is paid in errors and time. Here is the gap measured on the items that matter to a CFO.
| Criterion | Shared Excel files | Business app |
|---|---|---|
| Entry error rate | 3 – 5 % of cells | < 0.5 % (controls) |
| Monthly consolidation time | 8 – 20 h | < 1 h (real time) |
| Change audit trail | Near zero | Full log |
| Reliable concurrent access | No (conflicts) | Yes |
| Per-user permissions | No | Yes (roles) |
| Data-loss risk | High | Automatic backups |
| 3-year cost (15-person SME) | ~EUR 45,000 in lost time | EUR 30,000 + hosting |
Spreadsheet studies suggest up to 88 % of Excel files contain at least one error. On financial or stock data, one untracked error costs far more than the development.
Mini case study
Severine, CFO of a 22-person trading SME in Amsterdam, consolidated 6 Excel files into a master sheet every month. Time spent: 14 h/month for her and an accountant, plus recurring gaps with the books. She commissions a business app at EUR 34,000, delivered in 13 weeks: single entry, roles per department, dashboard and direct accounting export. Result: consolidation cut to 45 minutes/month, i.e. 160 h saved/year (~EUR 6,400), and no more closing gaps. Estimated payback at 26 months, excluding the reliability gain.
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FAQ
Why not keep Excel if it works?
Excel works until one untracked error skews a close or a decision. As an order of magnitude, a 15-person SME loses the equivalent of EUR 45,000 over 3 years in consolidation time and fixes.
How long to develop the app?
Count 10 to 16 weeks depending on the number of processes and roles. A single-process scope fits in 10-12 weeks; multi-department management with approvals climbs to 14-16 weeks.
Can existing Excel data be migrated?
Yes, data migration is part of the project. We clean, structure and import history, typically for EUR 2,000 to 5,000 depending on volume and file quality.
What are roles and permissions?
They are per-user permissions: who sees what, who can edit, who approves. That's what Excel sorely lacks and what protects your sensitive data (HR, finance, margins).
What maintenance budget should I plan?
Count 12 to 18 % of development cost per year for evolutions, hosting and support. On a EUR 34,000 app, that's about EUR 4,000 to 6,000/year.
Let's scope your project. List the Excel files to replace, your number of users and roles, and we'll price the app and the reliability gain. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.
Mohamed Bah
Fondateur, Kolonell
Passionate about digital and entrepreneurship in Africa, Mohamed has been helping Sénégalese businesses with their digital transformation since 2020. Founder of Kolonell, he believes every SME deserves a professional and accessible online présence.
