The verdict in three sentences
An ERP-CRM connector removes double entry on roughly 1,800 records/month and cuts desync from 6 %/month to under 0.5 %. A subscription iPaaS (Make Pro €100 to €300/month for 40 to 100k operations) sets up fast; a custom bidirectional API connector (€9,000 to €18,000) handles complex business cases with no operation cap. Plan for 4 to 7 weeks and 20 to 30 hours/month saved.
Subscription iPaaS vs custom connector
iPaaS is perfect for simple flows and moderate volume; custom takes over as business rules (dedup, complex mapping, high volume) get denser.
| Criterion | iPaaS (Make/Zapier) | Custom connector |
|---|---|---|
| Initial build | €500 – €2,000 | €9,000 – €18,000 |
| Monthly cost | €100 – €300 | Hosting €80 – €200 |
| Operation cap | 40 – 100k/month | Unlimited |
| Complex business rules | Limited | Custom |
| Time to launch | 2 – 3 weeks | 4 – 7 weeks |
| Sync | Often one-way | Bidirectional real-time |
| Maintenance | Included | €400 – €750/month |
The cost of double entry
Double entry isn't just lost time: it breeds costly errors. 2026 order-of-magnitude estimate for ~1,800 synced records/month.
| Item | Before connector | After connector |
|---|---|---|
| Re-keyed records/month | 1,800 | 0 |
| Entry hours/month | 26 | 3 |
| Desync rate | 6 % | <0.5 % |
| Erroneous records/month | 108 | 9 |
| Error correction cost/month | €540 | €45 |
| Entry labor cost/month | €1,040 | €120 |
| Total monthly cost | €1,580 | €165 |
Mini case study
Marc, IT director at a trading SMB in Montreal, juggles Odoo (ERP) and a separate CRM. His teams re-key 1,800 records/month and fix around a hundred stock errors. With a custom bidirectional connector at €13,000, double entry disappears and desync falls below 0.5 %. Monthly saving: ~€1,400 in time and corrections. Including maintenance, payback lands at ~11 months, with a reliability gain that's hard to quantify on the customer side.
FAQ
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Isn't an iPaaS like Make enough?
For simple flows under ~40k operations/month and one-way sync, yes. Once you need real-time two-way sync, dedup or business rules, custom avoids caps and fragile workarounds.
Which systems can be connected?
Odoo, Sage, Dynamics on the ERP side; HubSpot, Salesforce, Pipedrive on the CRM side. Any system exposing a REST API or accessible database can be linked.
How are data conflicts handled?
A priority rule (source of truth per field) plus a timestamp settle conflicts. Ambiguous cases are logged for review without blocking the sync.
What's the implementation timeline?
Plan 4 to 7 weeks: field mapping, bidirectional mapping development, testing on real data, then a gradual switchover with dual control.
What does maintenance cover?
Maintenance (€400 to €750/month) covers vendor API changes, new fields, flow monitoring and incident recovery.
Let's scope your project. Specify your ERP, your CRM and the record volume to sync: we'll price the connector and the ROI. 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.
