The verdict in three sentences
Custom construction software only makes sense if it matches your quantity surveys, price schedules and purchasing processes — otherwise a SaaS is enough. In 2026, expect a quoting/site-management core of 45,000 to 75,000 EUR excl. tax, plus 15,000 to 35,000 EUR of modules as needed. The return comes from two levers: quoting twice as fast and margin per project visible live, not at year-end.
The budget module by module in 2026
A custom project splits into a core plus modules switched on by maturity. Here are the 2026 orders of magnitude for a Marseille works company of 30 to 60 employees.
| Building block | 2026 budget (EUR excl. tax) | Timeline |
|---|---|---|
| Quoting + site core | 45,000 - 75,000 | 3 - 4 months |
| Quantity-survey module | 8,000 - 18,000 | +4 - 6 wks |
| Gantt planning module | 6,000 - 14,000 | +3 - 5 wks |
| Purchasing/subcontracting module | 7,000 - 16,000 | +4 - 6 wks |
| Price schedule import | 4,000 - 9,000 | +2 - 3 wks |
| ERP/accounting integration | 6,000 - 15,000 | +3 - 5 wks |
| Offline site mode | 5,000 - 12,000 | +3 - 4 wks |
A realistic first-year scope (core + quantity survey + purchasing + accounting integration) therefore lands around 66,000 to 124,000 EUR excl. tax. Annual maintenance (support + hosting) then represents 12 to 18 % of the development cost.
What custom really changes
The difference does not show in a demo but in daily execution speed. Here are the 2026 gains measured on comparable deployments.
| Lever | Before (Excel/paper) | After (custom) | Gain |
|---|---|---|---|
| Time to quote a bid | 6 - 10 h | 3 - 5 h | -50 % |
| Project margin visibility | End of project | Real time | Earlier decisions |
| Quantity-survey errors | Frequent | Rare | -70 % rework |
| Purchasing tracking | Scattered | Centralized | -15 % overuse |
| Progress claims invoiced | Late | On time | Cash flow +10-20 days |
Mini case study
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Sofiane manages a 42-employee finishing-works firm in Marseille with 6.5M EUR revenue. His estimating office produces around 220 bids a year, each requiring 8 hours of survey and quoting. At 45 EUR/hour loaded, that is 79,200 EUR/year of quoting time.
By investing 72,000 EUR excl. tax in a custom core with a quantity-survey module and price-schedule import, Sofiane halves quoting time, saving 39,600 EUR a year. Add real-time margin tracking that let him stop two loss-making projects before they spiralled (estimated 40,000 EUR of losses avoided in year one). The project pays for itself in under 14 months, and the tool is his.
FAQ
Why pay 70,000 EUR when a SaaS costs 50 EUR/month? Because a SaaS imposes its processes; if your surveys and schedules are specific you waste time working around the tool. Custom aligns with how you quote and belongs to you for life.
Can we reuse our price libraries? Yes, importing schedules (4,000 to 9,000 EUR) is part of scoping. Your current Excel files become the basis of the price library configured in the tool.
Does offline mode work on every site? Yes, the app stores data locally and syncs when the network returns. It is essential on poorly covered sites, otherwise your teams revert to paper.
How much is maintenance? Expect 12 to 18 % of development cost per year for support and hosting, roughly 9,000 to 13,000 EUR/year on a 72,000 EUR project. That budget covers fixes, upgrades and secure hosting.
How long until go-live? The core ships in 3 to 4 months, modules are added incrementally afterwards. Plan a pilot on a real site before full rollout, so 5 to 7 months total.
Let's scope your project. Send us a sample of your price schedules and your current software stack (accounting, payroll, ERP) and we'll scope the core + modules 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.
