Ask for a complete cost schedule, not a single minute rate. Our recommended quote decoder separates usage, fixed fees, implementation, internal operation and failure recovery.
| Cost category | Questions to resolve |
|---|---|
| Usage | What starts and stops the meter? What happens during silence, hold, voicemail and transfer? |
| Telephony | Which numbers, call legs, destinations and carrier charges are included? |
| Capacity | What happens when simultaneous-call limits are reached? |
| Configuration | Who writes the rules, builds integrations and performs acceptance testing? |
| Support | What response commitments apply outside business hours? |
| Governance | Are required permissions, identity controls and data settings in the quoted tier? |
| Quality operation | Who reviews failures, retests changes and maintains approved knowledge? |
| Recovery | Who pays for repeat calls, corrections and human rescue? |
| Exit | What can be exported, and what work or fees are needed to leave? |
Billing differences are documented, not merely hypothetical. Retell says silence is billable and that its AI fee stops after transfer while telephony charges continue. Bland documents separate transfer charges and a Bring Your Own Twilio exception. Obtain a worked invoice for your exact call path rather than assuming those models are interchangeable. (retellai.com)
Any ambiguity should be resolved in the order form or pricing schedule before production traffic begins.