TAC can accept ITIN renewal applications in person.  Your client should verify using the link below that the TAC he/she intends to make an appointment for can authenticate supporting documents for W-7.  Otherwise, the original or certified documents will still need to be submitted.

https://www.irs.gov/help/tac-locations-where-in-person-document-verification-is-provided

Alternatively, your client may use one of the Certifying Acceptance Agents listed in the following link without an asterisk.  Those who are listed with an asterisk are Acceptance Agents only and they cannot certify documents.  As you may already be aware, these Certifying Acceptance Agents are almost always tax professionals who compete with you for business.

https://www.irs.gov/individuals/international-taxpayers/acceptance-agent-program