The strongest candidate is usually the handoff between lead capture and the main record: contact details, property, assigned person and last action should move together. A listing import that only copies the address and price still leaves plenty of rekeying.
Before comparing tools, map one...
Also pin down the exact municipality rather than relying on “near Jakarta” or “country home.” Ask for copies of the current annual property-charge records and confirmation of any unpaid amounts attached to the property. I would also separate government charges from estate, access, maintenance or...
Permission controls can also recreate duplicate entry indirectly. If the person arranging a viewing cannot correct a phone number or accessibility detail, they may keep a separate note rather than wait for an administrator. The trial should include ordinary exceptions, not just the clean demo path.