The verdict in three sentences
A custom API integration between your site, your ERP (SAP, Sage, Odoo) and your CRM (Salesforce, HubSpot) costs 6,000 to 15,000 EUR for a simple flow, 15,000 to 40,000 EUR for a multi-flow integration with middleware, and 40,000 to 90,000 EUR for critical real-time sync. Timelines run 6 to 16 weeks. The key trade-off: custom build for robustness and ownership, or iPaaS (500-3,000 EUR/month) to start fast on standard flows.
Why integrations cost what they cost
An integration is never "just connect two tools". Cost comes from data transformation (each system has its own model), error handling (what happens if the ERP is down?), volumes and frequency (nightly batch vs real time). A "new order on site → ERP" flow is simple; syncing stock, pricing, customers and invoices in real time across three systems is a project in itself.
The quality of an integration is measured by its ability to lose nothing: idempotency, queues, automatic retry. It is invisible when all goes well and vital when a system fails.
Cost by flow type (2026, order of magnitude)
| Integration type | Scope | Cost (EUR) | Timeline |
|---|---|---|---|
| Simple (1 flow) | Site orders → ERP | 6,000 – 15,000 | 6 – 8 wks |
| Medium (multi-flow) | Products, stock, customers, middleware | 15,000 – 40,000 | 8 – 12 wks |
| Complex (real-time) | Bidirectional sync, iPaaS, 3+ systems | 40,000 – 90,000 | 12 – 16 wks |
| Add a connector | New system on existing base | 4,000 – 12,000 | 3 – 5 wks |
Recurring: maintenance 600 to 2,000 EUR/month to monitor flows and absorb vendor API changes, which happen regularly.
Custom build vs iPaaS (Make, Workato)
| Criterion | iPaaS (Make, Workato) | Custom integration |
|---|---|---|
| Entry cost | 500 – 3,000 EUR/month | 6,000 – 90,000 EUR one-off |
| Standard flows | Fast to connect | Custom |
| Complex business logic | Limited | Unlimited |
| High volume / real time | Costly at scale | Optimized |
| Lock-in | High (platform) | None (owned code) |
| 3-year cost (medium flow) | 18,000 – 108,000 EUR | 15,000 – 40,000 EUR + maintenance |
iPaaS excels for standard, low-volume flows you need to connect fast. But cost climbs with the number of operations: past a certain volume, or as soon as business logic becomes specific, a custom build amortizes and makes you independent.
Mini case study
Sophie, IT director of a 90-person distribution SME in Berlin, deals with manual re-entry between her e-commerce site, her Sage ERP and HubSpot. Two people spend around 30 hours/month copying orders and customer records, with a 4 percent error rate generating disputes. A medium integration at 28,000 EUR removes the re-entry: she saves around 900 EUR/month in time and cuts errors from 4 percent to under 0.5 percent. With avoided disputes, the integration pays back in around 24 months, and data becomes reliable in real time.
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FAQ
How much does an API integration cost in Berlin in 2026?
A simple flow (site orders → ERP) costs 6,000 to 15,000 EUR. A multi-flow integration with middleware rises to 15,000 – 40,000 EUR, and critical real-time to 40,000 – 90,000 EUR.
What timeline for an ERP/CRM integration?
6 to 16 weeks depending on complexity: 6-8 weeks for a simple flow, 12-16 weeks for real-time sync across three systems.
Should I choose iPaaS or custom integration?
iPaaS (500-3,000 EUR/month) suits standard, low-volume flows. As soon as business logic is specific or volumes are high, custom amortizes over 2-3 years and removes lock-in.
What happens if the ERP goes down during a flow?
A robust integration uses queues and automatic retry: nothing is lost, everything is replayed on recovery. This is exactly what custom handles better than basic iPaaS scenarios.
What recurring cost after go-live?
Maintenance costs 600 to 2,000 EUR/month. It is essential because vendor APIs (SAP, Salesforce, HubSpot) evolve and can break an unmaintained flow.
Let's scope your project. List your systems (ERP, CRM, site), flows and volumes; we'll frame a simple (6-15k EUR) to complex (40-90k EUR) integration. 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.
