The verdict in three sentences
For an Amsterdam developer, running programs, units, reservations and milestone billing in spreadsheets always ends up costing dearly in errors and mistimed cash. A custom build at EUR 38,000-85,000 centralizes sales, the buyer portal (fit-out/handover tracking) and per-program financial reporting. ROI hinges on cash-flow and sales velocity, not license price.
What does development software cost in Amsterdam in 2026?
Two options: market verticals, often rigid on milestone billing, or a build aligned to your financial structure. 2026 orders of magnitude:
| Solution | Upfront cost | Recurring | Buyer portal |
|---|---|---|---|
| Development vertical | EUR 8,000-15,000 setup | EUR 90-150/user/mo | Standard |
| Real-estate ERP suite | EUR 20,000-40,000 | EUR 200-400/mo | Limited |
| Kolonell custom build | EUR 38,000-85,000 | EUR 400-800/mo hosting | Custom, on your brand |
For a 6-user developer, a EUR 120/month vertical is EUR 8,640/year, while you never own the milestone-billing logic specific to your programs.
Which scope to prioritize?
Build from the most structural (sales, cash) toward comfort (portal). Typical pricing:
| Module | Scope | Estimate |
|---|---|---|
| Programs & units | Price grid, inventory, statuses | EUR 8,000-15,000 |
| Reservations & sales | Options, contracts, notary | EUR 7,000-14,000 |
| Milestone billing | Milestone schedule, reminders | EUR 8,000-16,000 |
| Buyer portal | Build tracking, fit-out, documents | EUR 9,000-18,000 |
| Financial reporting | Margin/program, cash | EUR 8,000-17,000 |
Bank/notary integration (document exchange, releases) and per-program reporting are what separate a genuine development tool from a plain CRM.
Mini case study
Sarah is a program director at an Amsterdam developer: 4 active programs, 180 units/year. Her milestone billing takes 3 days of re-keying per program and causes cash delays. She invests EUR 62,000 in a custom tool. Automated milestone billing speeds collections by 22 days on average, cutting working-capital needs by EUR 340,000 across live programs. The tool pays back within the first program cycle.
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FAQ
Doesn't a market vertical already do all this?
It covers sales, but often stumbles on each developer's milestone-billing logic and a branded buyer portal. Custom wins the moment those two points are strategic.
How long to implement?
Allow 4 to 7 months for the full scope. The programs/units and reservations module can ship in 8-10 weeks to start selling the first program.
Can we give buyers access?
Yes, the buyer portal enables build tracking, fit-out choices, document signing and billing milestones, on your brand.
How does bank and notary integration work?
Via secure document exchange and release tracking. Exact scope depends on your partners; we frame it in the quote.
Does it handle multiple programs in parallel?
Yes, each program has its own inventory, schedule and financial reporting, with a consolidated multi-program cash view.
Let's scope your project. Tell us your number of programs, your milestone-billing setup, and your bank/notary partners; we'll frame a scope and budget between EUR 38,000 and 85,000. 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.
