Custom Business Platform vs Odoo in Amsterdam: 2026 Cost Comparison

The verdict in three sentences

For an SME with 70 staff and 45 users, Odoo Enterprise remains the best choice as long as more than 80% of your processes fit the standard modules. Once the core business (here, construction site management) requires heavy custom development, a custom platform at EUR 45,000 to 110,000 excl. VAT becomes cheaper over 5 years and frees you from integrator lock-in. The most cost-effective answer is often hybrid: Odoo for accounting and payroll, custom for site operations.

Why construction sites break standard ERPs

A fit-out or construction SME in Amsterdam deals with realities that general ERPs model poorly: progress billing by work package, subcontractors under VAT reverse charge, 5% retention, crews clocking in on several sites per day, photos and snagging lists at handover. Odoo handles accounting, purchasing and inventory well. The Project module, however, needs significant adaptation to track monthly progress valuations. Every adaptation is custom code that must be maintained at each annual version upgrade.

The 5-year cost comparison

Assumption: 45 users, 2026 Odoo Enterprise public pricing between EUR 31 and 47 per user per month depending on plan and hosting.

The ranges overlap: the right decision depends on standard coverage. These are 2026 orders of magnitude observed in SMEs of 50 to 100 staff.

The criteria that tip the decision

The hybrid scenario combines both columns: Odoo Accounting and Purchasing (10 to 15 back-office users, so fewer licences) plus a custom site app for the 30 field users, linked by API.

Mini case study

Marc, CFO of a 70-person interior fit-out company in Amsterdam, compares two offers for 45 users.

• Odoo at EUR 39 per user: EUR 21,060 a year, or EUR 105,300 over 5 years, plus EUR 28,000 integration, EUR 22,000 of site modules and EUR 9,000 of annual support (EUR 45,000). Total: EUR 200,300.
• Custom: EUR 78,000 excl. VAT build, EUR 11,700 annual maintenance from year 2 (EUR 46,800) and EUR 3,000 hosting a year (EUR 15,000). Total: EUR 139,800.
• Hybrid chosen: Odoo for 12 back-office users (EUR 28,080 over 5 years, EUR 12,000 integration) and a custom site app at EUR 52,000 excl. VAT with EUR 31,200 of maintenance. Total: EUR 123,280.

The hybrid saves EUR 77,000 compared with full Odoo and keeps standard accounting that the external accountant already knows.

FAQ

Does free Odoo Community change the math?

It removes licences, but full accounting and several key modules are Enterprise-only. The adaptations to maintain stay the same, so budget EUR 20,000 to 50,000 of extra development.

How long does a custom platform take to deliver?

4 to 6 months for a full site-management scope: 3 weeks of scoping, 12 to 18 weeks of sprint development, 3 weeks of acceptance on 2 pilot sites.

Can we migrate data from an existing ERP?

Yes, migrating customers, ongoing projects, suppliers and items takes 1 to 3 weeks depending on data quality. Budget EUR 3,000 to 8,000 excl. VAT.

Does the site app work without a network?

Yes, in offline mode: clock-ins, photos and snags are stored on the phone and synced when the network returns. This is a frequent weakness of generic ERPs on basement sites.

Who maintains the platform if the agency disappears?

You receive the source code, documentation and access. A third-party team can take over in 3 to 4 weeks, often faster than switching Odoo integrators.

Let's scope your project. Send us your process list and user count: we will compare Odoo, custom and hybrid over 5 years, with a budget between EUR 45,000 and 110,000 excl. VAT and a 3 to 6 month timeline. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.