The verdict in three sentences
A construction or development SME in London can run its sites on a construction SaaS (35-80 EUR/user/month), but custom software (55,000-130,000 EUR) becomes necessary once cost tracking and progress billing must match your process. The site tracking module (10,000-22,000 EUR) and the accounting/payroll connector (6,000 EUR) are the lines that turn reporting into time saved. The trade-off comes down to site reporting hours saved.
Construction SaaS or custom: the cost lines
Construction SaaS starts fast but imposes its own tracking templates. Custom fits your progress billing, your cost breakdown and your site-margin indicators. 2026 orders of magnitude for a 15-user London SME.
| Item | Construction SaaS | Custom build |
|---|---|---|
| Build / initial license | 0 EUR (subscription) | 55,000-130,000 EUR |
| Monthly cost per user | 35-80 EUR | included in maintenance |
| Site tracking + progress billing | often partial | 10,000-22,000 EUR |
| Accounting / payroll connector | add-on | 6,000 EUR |
| Monthly maintenance | included | 1,200-3,000 EUR |
| Vendor day rate | — | 550-750 EUR |
| Time to go live | 3-6 weeks | 14-24 weeks |
The decisive line is progress billing tracking: without it, budget overruns surface too late. A custom module surfaces site margin in real time.
Three-year comparison (15 users)
| Scenario | Upfront | 3-year recurring | 3-year total |
|---|---|---|---|
| SaaS at 45 EUR/user | 0 EUR | 24,300 EUR | 24,300 EUR |
| SaaS at 80 EUR/user | 0 EUR | 43,200 EUR | 43,200 EUR |
| Custom 90,000 EUR + site tracking 16,000 EUR | 106,000 EUR | 72,000 maintenance | 178,000 EUR |
SaaS stays lighter, but custom changes things once a single avoided overrun per site exceeds the extra cost. On projects worth hundreds of thousands, early detection pays quickly.
Mini case study
Julien runs a 15-person construction SME in London with 6 concurrent sites. He invests 90,000 EUR in custom software with a site tracking module (16,000 EUR) and 2,000 EUR/month maintenance. Site managers save 4 hours per week each on reporting and reconciling progress statements. At 42 EUR/loaded hour across 4 managers that is 4 × 4 × 42 × 45 weeks = 30,240 EUR/year, plus early overrun detection: a single 2% overrun avoided on an 800,000 EUR site is worth 16,000 EUR. The build pays back in two to three years.
FAQ
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Is a construction SaaS enough for a small SME?
To run quotes, purchasing and scheduling, a SaaS at 35-45 EUR/user/month works. Custom becomes necessary when analytical tracking and progress billing are too specific.
What does the site tracking module cost?
Between 10,000 and 22,000 EUR depending on detail (progress statements, real-time margin, variations). It is the best-ROI line.
Can accounting and payroll be connected?
Yes, budget around 6,000 EUR for an accounting/payroll connector that avoids double entry and firms up cost tracking.
How long for custom construction software?
From 14 to 24 weeks depending on scope (sites, purchasing, progress billing, mobile). Precise scoping limits overruns.
What gain on site reporting?
Around 3 to 4 hours per site manager per week, plus early overrun detection which alone can repay the project.
Let's scope your project. Tell us your number of sites, users and analytical tracking needs: we will cost out the most profitable scenario, indicative budget 55,000-130,000 EUR by scope. 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.
