The verdict in three sentences
A custom ERP-CRM connector automatically moves customers, orders and stock between your two systems, with no re-keying or manual export. For an Amsterdam IT manager, budget 10,000 to 35,000 EUR (excl. VAT) per connector depending on the number of synced objects and conflict-rule complexity. The ROI is direct: no more double entry, reliable data, and no gap between sales and logistics.
Connector price in 2026
Cost tracks the number of objects to sync (customers, products, orders, stock, invoices) and the flow direction. Two-way sync with conflict handling costs notably more than a simple one-way flow.
| Scope | Synced objects | Direction | Price EUR (excl. VAT) | Timeline |
|---|---|---|---|---|
| Basic | 1 to 2 objects | One-way | 10,000 - 15,000 | 4 - 5 wks |
| Standard | 3 to 4 objects | Two-way | 15,000 - 25,000 | 6 - 8 wks |
| Advanced | 5+ objects, conflicts handled | Two-way real time | 25,000 - 35,000 | 8 - 10 wks |
| Complex | Multi-system, middleware | Orchestration | 35,000+ | 10 wks+ |
Add annual monitoring of 12 to 18 % of the build to handle API changes and sync-failure alerts, i.e. 1,500 to 6,000 EUR (excl. VAT) per year.
Conflict handling: the real issue
The hard part is not copying data, it is deciding who wins when both systems diverge. A clear strategy avoids wild overwrites.
| Strategy | Principle | Use case |
|---|---|---|
| Source of truth | One system rules per object | Customers = CRM, stock = ERP |
| Last write wins | Most recent timestamp | Low-sensitivity fields |
| Field-level merge | Each field has an owner | Shared rich records |
| Queue + validation | Conflict held for human review | Critical data (pricing) |
Defining these rules is 15 to 20 % of project effort but prevents costly post-launch incidents.
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Mini case study
Karim is IT manager at an industrial SME in Amsterdam, 70 staff. Sales reps enter orders in the CRM, then back-office re-keys them into the ERP: about 15 minutes per order, 600 orders/month. We deliver a Standard two-way connector at 21,000 EUR (excl. VAT) in 7 weeks.
Maths: 600 x 15 min = 150 hours/month eliminated, i.e. 1,800 hours/year. At 30 EUR/hour loaded, that is 54,000 EUR saved per year, not counting re-keying errors (addresses, quantities) that caused returns. The connector pays back in under 5 months.
FAQ
Why custom rather than an iPaaS like Zapier? For high volumes and business conflict rules, no-code platforms get expensive and fragile. A dedicated connector costs more upfront but stays stable and cheaper to run beyond a few thousand operations/month.
How long for the first sync? A simple one-way flow works in 4 weeks; two-way with conflicts takes 6 to 10 weeks.
What if an API goes down? The connector queues operations and replays automatically, with alerts. We guarantee no data is lost during an outage.
Must I modify the ERP or CRM? Rarely. We use existing APIs; if they are missing, an intermediate database avoids touching the core tools.
Can a connector evolve? Yes, we add objects or rules incrementally. Budget 15 % per year for evolutions and monitoring.
Let's scope your project. List the objects to sync and the desired direction, and we'll price a connector within the 10,000-35,000 EUR range. 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.
