Create a test client in Invoice Ninja and take a job from quote to invoice, partial payment, reminder, credit, and final reconciliation. Check numbering, taxes, currency, PDF output, and the exact payment status shown to the client. Compare totals to an independent calculation.
Before migrating, test contact import, invoice export, and a restore from backup. Financial records need a traceable correction path; avoid editing historical invoices in ways that obscure what a customer originally received. Confirm the local tax and recordkeeping requirements with your accountant.
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