The verdict in three sentences
A software vendor in Amsterdam that wants to serve 200 client companies with its reporting tool should budget between EUR 37,000 and EUR 83,000 excl. VAT for a solid multi-tenant platform. The item that moves the bill is the data isolation model: shared schema with strict filtering, schema per client or database per client. Add EUR 460 to EUR 1,400 per month for hosting and a GDPR data processing agreement, otherwise your first enterprise accounts will not sign.
Three isolation models, three cost levels
The question your prospects' IT leads always ask is the same: "can my numbers ever show up in a competitor's account?". The technical answer drives the budget, the maintenance load and your ability to sell to banks or industrial groups.
| Isolation model | Principle | 2026 build cost | Monthly hosting (200 clients) | Best-fit client |
|---|---|---|---|---|
| Shared database + app-level filtering | A client_id column on every table | EUR 37,000 to 48,000 | EUR 460 to 650 | Small businesses, entry plans |
| Shared database + Row Level Security | Security policy enforced in the database | EUR 44,000 to 57,000 | EUR 550 to 740 | Demanding SMEs, firms |
| Schema per client | One PostgreSQL schema per company | EUR 53,000 to 69,000 | EUR 740 to 1,000 | Mid-market, retail, industry |
| Dedicated database per client | Isolated database, own encryption keys | EUR 64,000 to 83,000 | EUR 1,000 to 1,400 | Banks, insurers, groups |
| Hybrid (shared + dedicated premium) | Shared by default, dedicated as paid option | EUR 60,000 to 78,000 | EUR 650 to 1,200 | Vendor targeting several segments |
Our recommendation for 200 clients: Row Level Security as the foundation, with a dedicated-database option sold as an upgrade to regulated accounts. You keep a single codebase, simple migrations and a clear premium sales argument.
What the budget actually covers
The dashboard the user sees rarely accounts for more than a third of the effort. The rest is the infrastructure that lets you sell, bill and administer 200 accounts without hiring a ten-person support team.
| Component | Scope | Share of budget | 2026 range (EUR excl. VAT) |
|---|---|---|---|
| Multi-tenant engine | Isolation, roles, invitations, client subdomains | 20 % | 7,400 to 16,600 |
| Data connectors | Excel import, ERP APIs (Exact, Odoo), SQL databases | 18 % | 6,700 to 14,900 |
| Dashboards and exports | Charts, filters, scheduled PDFs, white label | 25 % | 9,200 to 20,700 |
| Subscription billing | Plans, trials, SEPA and cards, compliant invoices | 12 % | 4,400 to 10,000 |
| Vendor console | Account monitoring, quotas, support, access logs | 10 % | 3,700 to 8,300 |
| Security and GDPR | Encryption, audit logging, records, DPA | 8 % | 3,000 to 6,600 |
| Testing, acceptance, go-live | Automated isolation tests, load, documentation | 7 % | 2,600 to 5,800 |
The item most often forgotten: automated isolation tests. Every new feature must be checked by a script that tries to read another client's data. That is what protects your reputation the day a developer forgets a filter.
Billing, hosting and GDPR
For billing, most Dutch vendors combine card and iDEAL payments for small accounts with annual invoicing by SEPA transfer for enterprises. A realistic 2026 price sits between EUR 140 and EUR 550 excl. VAT per month per client depending on users and connected data sources.
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On hosting, an EU-based infrastructure with encrypted backups, a staging environment and monitoring costs EUR 460 to EUR 1,400 per month. If your clients are financial institutions, expect questions about data residency in the EU and sub-processors located outside it.
GDPR requires a record of processing, a data processing agreement with each client and appropriate security. In practice your SaaS contract needs an annex stating data location, retention periods and the breach notification procedure (72 hours to the Dutch Data Protection Authority).
Mini case study
Daan, founder of a reporting software company in Amsterdam, currently serves 35 clients with one installation per client. Each update takes him 2 days per client, or 70 working days per release. He opts for a Row Level Security platform at EUR 51,000 excl. VAT and hosting at EUR 690 per month.
With 200 clients at an average of EUR 260 excl. VAT per month, recurring revenue reaches EUR 52,000 per month. Annual hosting (EUR 8,300) is under 2 % of revenue. The build is paid back in one month at full load, and in about 8 months on a gradual ramp from 35 to 200 clients. Updates drop from 70 days to a single deployment day.
FAQ
How long does the multi-tenant version take to launch? Plan 4 to 6 months for a full scope with billing and vendor console. A first version for 20 pilot clients can ship in 12 to 14 weeks.
Can we migrate current clients without downtime? Yes, with one migration script per client and a scheduled cutover outside business hours. Plan 1 to 2 hours per client and a 2-week parallel run.
Is Row Level Security enough for a bank? It provides strong isolation, but banks often ask for a dedicated database and their own encryption keys. Offer that tier as an option at EUR 280 to EUR 460 more per month.
What GDPR paperwork do we need? A record of processing, a DPA template for clients and a list of sub-processors. Preparing it usually takes 2 to 4 weeks and should be done before go-live.
How should we price the subscription? Start from cost to serve per client (hosting, support) and target a gross margin of 75 to 85 %. For 200 clients, an entry plan at EUR 140 and an enterprise plan at EUR 550 per month cover most cases.
Let's scope your project. We scope your multi-tenant reporting platform: isolation model, connectors, billing, an indicative budget of EUR 37,000 to EUR 83,000 and a 4 to 6 month plan. 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.
