Readers
Begin with the people who can access the service: you, colleagues, administrators and any provider staff authorised by its processes. Ask about role permissions and audit information. A product description using the word private may not explain these distinctions.
Copies
Forwarding, email notifications, downloads and screenshots can create additional copies. Understand what is copied, where it goes and how long it remains. Turning off a future notification does not necessarily remove an earlier copy.
Duration
Message retention, account duration and number allocation are separate timelines. A cancelled number may stop receiving for you while historic information remains elsewhere. Seek the provider’s retention and deletion explanation in writing.
Minimum detail
Ask general questions without submitting live phone numbers, login details or verification codes. If formal support needs identity evidence, use that organisation’s verified support process and provide only the information it legitimately requires.