Arm's length price certification requires accountant verification of similar transactions, unchanged risk allocation, and accurate disclosure. Certificate of an accountant for consent to determination of arm's length price under section 166 requires verification of the assessee's books, documents maintained under section 171, and other relevant records for the first tax year and the following two years. The accountant must certify that the case is not covered by Chapter XVI-B and that the transactions for which the option is exercised remain similar across the relevant tax years. The certificate also confirms no material change in functions, assets, risks, business results, holding structure, notified-jurisdiction residency, contractual terms, or the accuracy of Form No. 46 information.