You consolidate a tool stack in phases, not in one weekend migration. Start with the surfaces that share the most data and cause the most reconciliation work, prove the new system on live work before you switch off the old one, and keep accounting where it is. The goal is one connected record, reached one step at a time.
How do you consolidate an agency tool stack without disrupting client work?
The typical Dutch agency runs close to ten tools, each with its own monthly invoice: a shared inbox, a CRM, a pipeline, a projects tool, work and time tracking, visitor identification, de-anonymization, client reporting, and invoicing. None of them share a record, so the same client exists ten times and never quite matches.
That fragmentation is the real cost, and it is easy to underestimate. The subscriptions are the small number. The large number is the hours spent copying a deal into the projects tool, reconciling the reporting tool against the invoicing tool, and answering the question of which lead came from which campaign when the answer lives in four systems.
The first phase should be the spine that everything else references: the unified inbox and the lead-to-deal CRM. When every message and every deal resolves to one person record, you remove the largest source of double entry immediately, and you get a single history you can trust before you touch anything downstream.
The second phase is delivery and money: contracts, e-signature, invoicing, and payments. A signed contract that converts straight into an invoice removes a handoff that used to span two tools and a spreadsheet. Keep the client portal in this phase too, so clients have one place to pay, sign, and share files.
The third phase is the measurement layer, which is also the reason to bother: first-party tracking and server-side attribution wired to the same deals you just consolidated. Because the pipeline and the attribution now live in one system, the ad platforms can be told about conversions that actually closed.
Two rules keep delivery intact through all of this. Run the new surface in parallel on real work before you cancel the old subscription, so nobody is trapped mid-migration. And do not rebuild accounting: Metiva is built to connect to Moneybird and Exact Online, not to replace them. Consolidation is about ending the reconciliation tax, not about owning every last function.