The verdict in three sentences
A custom client portal for a property agency in Amsterdam costs 24,000 to 55,000 EUR in 2026, depending on the modules (documents, payments, messaging) and integration with the property management software. Expect a 9 to 14 week project and maintenance of 15 to 18 %/year. The gain: more than 10 hours/week saved on sending receipts and tracking files.
Cost per module
A property portal serves both landlords and tenants: viewing, paying, communicating. Here are the 2026 ranges for custom development.
| Module | Scope | Indicative 2026 cost (EUR) |
|---|---|---|
| Core + landlord/tenant accounts | Roles, MFA, dashboard | 5,500 - 10,000 |
| Document vault | Leases, inventories, diagnostics | 5,000 - 10,000 |
| Receipts & rent calls | Generation, automatic sending | 4,500 - 9,000 |
| Online payment | Rent, provisions, receipt | 4,500 - 9,500 |
| Messaging & file tracking | Threads per unit, statuses, alerts | 4,000 - 8,000 |
| Manager area | Tracking, reminders, exports | 4,000 - 8,000 |
A documents + receipts core starts around 24,000 EUR. A full portal with payment, messaging and a management-software connector reaches 49,000 to 55,000 EUR.
Management integration, security and maintenance
A property portal's value comes from its connection to the management software and data security (leases, ID documents). These items shape the budget over time.
| Item | Detail | 2026 order of magnitude |
|---|---|---|
| Management software connector | Units, rents, third parties | 6,500 - 15,000 EUR |
| Security & encryption | Sensitive documents, MFA, logs | 3,500 - 7,500 EUR |
| Secure EU hosting | Server, backups, certificates | 140 - 400 EUR/month |
| Maintenance | Fixes, evolutions, support | 15 - 18 %/year of budget |
| Payment gateway | Rent card/SEPA | fees 0.8 - 1.5 % + fixed |
For a 44,000 EUR project, maintenance represents 6,600 to 7,920 EUR/year.
Mini case study
Karim, director of an agency managing 620 units in Amsterdam, sent receipts and documents by post and email. Three property managers each spent around 10 hours/week on issuing and sending receipts, tracking payments and handling document requests, at an estimated loaded cost of 33 EUR/hour. That was 3 x 10 x 33 x 52 = 51,480 EUR/year of operational time. A portal at 44,000 EUR (documents + receipts + payment + messaging) that automates 60 % of this work saves around 31,000 EUR/year and makes collection more reliable. Estimated payback in under 20 months, with a clear improvement in landlord perception.
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FAQ
Can the portal send receipts automatically?
Yes: monthly generation, email delivery and posting to the tenant's area, with archiving. The receipts + rent calls module costs 4,500 to 9,000 EUR.
Can we collect rent online?
Yes, via a card/SEPA gateway with automatic receipt and reconciliation. Expect 4,500 to 9,500 EUR for the module, plus fees of 0.8 to 1.5 % per transaction.
Does it integrate with our management software?
Yes, via API or gateway to the main market tools. Cost depends on the vendor's openness: from 6,500 EUR for a documented API to 15,000 EUR for a complex integration.
Are sensitive documents secure?
Yes: encryption at rest, MFA, access logs and EU hosting. The dedicated security module costs 3,500 to 7,500 EUR and can include an annual audit.
How long until go-live?
Between 9 and 14 weeks, including migration of your management data and a testing phase with a few landlords and tenants.
Let's scope your project. Tell us your priority modules (documents, receipts, payment), your management software and your number of units, and we'll frame an indicative budget between 24,000 and 55,000 EUR. 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.
