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Data Integration|18 June 2026

Which system should be the source of truth for your customer data? A small‑team decision guide

A hands‑on 30–90 minute workshop and checklist to pick a single source of truth for key customer fields before connecting systems.

Run a short 30–90 minute workshop: agenda and outputs

  • 10–15 mins: agree scope — which customer records, which fields matter (contact, billing, lifecycle, consent) and who joins.
  • 20–40 mins: map each critical field to where it is most often updated and why (who types it, when, and what downstream uses it has).
  • 15–30 mins: choose a single owner per field, write simple sync rules and fallbacks, and pick two quick tests to validate.
  • 10 mins: note who owns the decision, where it’s documented, and a one‑line rollback if the sync misbehaves.

Outputs: a one‑page map (field → owner → sync direction → fallback), two short tests, and an owner to run them weekly for the first month.

Simple decision rules for common small‑team setups (HubSpot + Xero + a spreadsheet)

  • Contact details (email, phone, name): HubSpot is the primary. Let HubSpot push to Xero for invoices; use the spreadsheet only as a temporary capture source that feeds HubSpot, not as an authoritative record.
  • Billing information (invoice address, VAT number, payment status): Xero is primary for billing fields and payment status. Sync billing addresses from Xero to HubSpot so customer-facing teams see the invoice address, not the other way round.
  • Lifecycle stage and ownership: HubSpot owns lifecycle stage and contact owner. If Xero creates a customer record, send a webhook to create or update a HubSpot contact and let HubSpot set the lifecycle value.
  • Consent and marketing preferences: HubSpot should record consent (form sources, opt‑ins). If a spreadsheet captures verbal consent, record that in HubSpot rather than treating the sheet as the source.
  • Conflict and sync rules (short, practical): prefer the system where the value is maintained day‑to‑day (HubSpot for marketing/sales, Xero for finance), use timestamp wins for simple conflicts, and add a manual override flag for disputed records.
  • Fallbacks: if primary API fails, queue updates in the spreadsheet with a retry note; if the primary field is empty, read from the trusted secondary for a one‑off fill but do not change the owner.

Quick tests, monitoring and a documentation checklist

Run these quick tests after you switch a rule on: update a contact detail in the declared source and confirm the change appears in the other systems within the agreed window; create a new invoice in Xero and confirm HubSpot gets the billing address back; change a marketing preference in HubSpot and check it is not overwritten by a spreadsheet reimport.

Set simple monitoring: a weekly list of recently changed records with source stamps, a short Slack or email alert if sync errors appear, and a one‑line rollback plan (turn off the sync and mark records for manual review) that any team member can follow.

Document the choices on one page: the fields you picked, who owns each, sync direction and cadence, conflict rule, fallback, test steps and the date you reviewed it. If you want a focused session to run this with you and leave a one‑page map, Optira can help run the workshop and produce the checklist.

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