Peppol BIS 3.0 certifiedConfirm their Participant ID is active on the Peppol directory, Ask for a live test transmission, not a demo screen.
FTA-accredited Verify on the Ministry of Finance ASP registryIf they're not on the official list, nothing else they tell you matters.
UAE-specific experienceUnderstands PINT AE format and UAE VAT rules — including reverse charge, free-zone scenarios, and multi-currency invoicing.
Can handle your invoice volumeTest their stack at your peak monthly volume × 1.5. Get a written SLA on uptime and rejection-handling latency. Failed transmissions = failed invoices = unpaid bills.
Full invoice lifecycle supportRejections, corrections, and credit notes handled end-to-end. Ask them to walk through a credit note flow on a real ASP, not slides.
Native integration with your accounting systemNot a separate dashboard you log into and update by hand. If your finance team is double-keying invoices, you've bought a problem, not a solution.