1. The email domain does not match the company in the official registration record.
  2. The contact refuses a call-back on the registered phone number.
  3. Authority was granted very recently but the carrier claims years of history.
  4. The insurance certificate came from the carrier, not from the insurance agent.
  5. They ask for quick pay to a differently named company.
  6. They accept a rate far below the market without negotiating.
  7. The truck that arrives does not match the carrier's details.
  8. They pressure you to skip your normal process "just this once".
  9. Their authority status is inactive or revoked.
  10. They want pickup details changed by email at the last minute.

Practise spotting these in the Carrier Verification Simulator — and remember: verify through official sources, not through information the carrier sends you.