Cost audit reporting: auditors must submit prescribed reports and annexures to the designated authority and the company. Cost auditors must prepare and submit the cost audit report in the prescribed form with observations, suggestions and annexure, simultaneously forwarding a copy to the company; furnish a performance appraisal report to the Board/Audit Committee; and respond to clarification requests within thirty days. Companies specified for audit must maintain detailed cost records for each unit and product or activity, authenticated by at least two directors and the cost auditor, and retain such records in good order for not less than eight preceding financial years or for the period of the company's existence if shorter.