The verdict in three sentences
On a construction site, money leaks through invisible overruns: mis-recorded hours, unallocated equipment, costs discovered too late. A site management tool with a field mobile app delivers margin per site in real time: in 2026, expect 25,000 to 75,000 EUR custom or 20 to 60 EUR/user/month in SaaS. The major lever: cutting budget overruns by 10 to 20%.
The field app replaces paper sheets
The core of the gain is capture at the source: the worker clocks in and reports progress from their phone, the site manager sees costs live. Here are the 2026 orders of magnitude.
| Item | Site SaaS | Custom Kolonell |
|---|---|---|
| Entry cost | 0 to 3,000 EUR | 25,000 to 75,000 EUR |
| Monthly cost | 20 to 60 EUR/user | Hosting 100 to 300 EUR/month |
| 25-user company/year | 6,000 to 18,000 EUR | ~2,400 EUR (hosting) |
| Field mobile app | Standard | On your processes |
| Margin tracking per site | Often an add-on | Native |
| Time to go live | 3 to 8 weeks | 3 to 6 months |
For a 25-person company, SaaS costs 18,000 to 54,000 EUR over three years. Custom software is justified as soon as you want to match precisely your work types, timesheet rules and cost accounting.
The modules that protect margin
Construction profitability hinges on a few percentage points. Here are the high-impact modules, with a 2026 estimate.
| Module | Measurable effect | Annual estimate (25 people) |
|---|---|---|
| Geolocated mobile timesheets | -100% hour disputes | 15,000 to 40,000 EUR |
| Real-time cost tracking | -10 to -20% overruns | 50,000 to 150,000 EUR |
| Equipment/machinery allocation | -1 duplicate rental | 8,000 to 25,000 EUR |
| Site photos and reports | Reduced client disputes | Litigation avoided |
| Margin per site | Fast corrective decisions | Strategic |
Real-time cost tracking is the module that pays for the project: on an order book of a few million euros, saving even 2 points of overrun represents tens of thousands of euros.
Mini case study
Karim, a site manager at a 25-employee structural works company, ran 6 simultaneous sites with annual revenue of 3.2M EUR. His average overruns hovered around 9%, i.e. ~288,000 EUR of margin eroded per year, discovered at the end of each site.
He invests 58,000 EUR in custom software with mobile timesheets and real-time cost tracking. By bringing overruns from 9% down to 6%, the company recovers 3 margin points, i.e. ~96,000 EUR/year. The project pays for itself in about 8 months, including 200 EUR/month of hosting.
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FAQ
How much does custom site management software cost?
In 2026, expect 25,000 to 75,000 EUR depending on modules (timesheets, costs, equipment, reports) and the number of work types. A useful starting scope begins around 25,000 EUR.
Does the field app work offline?
Yes: timesheet and progress entry happen offline and sync as soon as the network returns. Essential on poorly covered sites.
By how much do budget overruns drop?
By 10 to 20% in general, simply because the site manager sees costs in real time and corrects before it is too late. On multi-million revenue, the effect runs into tens of thousands of euros.
Do mobile timesheets reduce hour disputes?
Yes: each hour is declared at the source, geolocated and timestamped. Disputes over worked hours and temporary staff almost disappear.
How long does deployment take?
Expect 3 to 6 months depending on scope, with a first version (timesheets + cost tracking) deliverable in 8 to 10 weeks.
Let's scope your project. Tell us your field headcount, the number of simultaneous sites and your priorities (timesheets, costs, equipment) with an indicative budget. 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.

