The verdict in three sentences
A construction firm bills by progress statement: percentage completion, a 5 % retention, price revision and site payment terms of 45 to 90 days. Generic invoicing software is not built for this and pushes teams into Excel, a source of costly errors. A custom progress-billing app removes around 80 % of errors and protects your cash flow.
Excel versus a construction billing app
Excel handles arithmetic but not the business logic: cumulative statements, retention, revision, VAT on completion. A statement error on a contract worth hundreds of millions quickly means millions of FCFA lost or a dispute with the client.
| Criterion | Excel | Construction billing app |
|---|---|---|
| Cumulative statements | Manual, risky | Automatic |
| 5 % retention | Recalculated | Tracked per contract |
| Price revision | Fragile formula | Built in |
| Statement errors | Frequent | -80 % |
| 45-90 day receivables | Absent | Dashboard |
| History per contract | Scattered files | Centralized |
On a tracked contract of 20 to 500 M FCFA, even a 1 % statement error can cost millions — the app pays for itself on a single project.
2026 budget: build or SaaS
Few SaaS tools handle Senegalese-style progress billing (retention, revision, public payment orders). The custom build fits your statement templates and your clients. 2026 order of magnitude.
| Item | Custom build | Monthly SaaS |
|---|---|---|
| Upfront cost | 1,800,000 - 3,500,000 FCFA | Low |
| Recurring cost | Hosting only | 15,000 - 40,000 FCFA/month |
| Statement templates | Custom | Generic |
| Retention + revision | Included | Rare |
| Time to go live | 7 - 11 weeks | 2 - 3 weeks |
| Data ownership | You | The vendor |
At 30,000 FCFA/month, SaaS costs 360,000 FCFA/year while never matching your regulated statements; the build typically amortizes in two to three years while removing error risk.
Mini case study
Fatou runs a construction firm in Thies tracking 4 sites worth 180 M FCFA in total. In Excel, a price-revision error made her under-bill one statement by 2,400,000 FCFA, recovered only through a three-month dispute. With the progress-billing app (a 2,600,000 FCFA build), every statement automatically compounds retention and revision. A single avoided error covers the app, and tracking retention (9,000,000 FCFA locked at 5 %) lets her claim its release on time.
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FAQ
Does the app handle retention and its release?
Yes. Each statement automatically withholds the contractual 5 %, compounds the locked amount and flags the release date (often 12 months after handover). You never lose forgotten retention again.
Can it manage price revision by index?
Yes. Revision formulas (construction indices, coefficients) are configured per contract and applied to each statement, replacing fragile Excel formulas.
Does the app produce a compliant statement for a public client?
Yes. Statement and general-account templates follow the expected format (completion, cumulative, VAT, retention), ready to submit for payment.
How are 45-90 day receivables tracked?
A dashboard shows every issued statement, its due date and status. You follow up on time and shorten your collection period.
How long to go live?
Expect 7 to 11 weeks depending on how many contract templates to integrate. A first pilot site runs from week six.
Let's talk about your project. We model your statements, retention and price revision in one call. 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.
