If the price of a vehicle body or a major part of a special-style vehicle declared by the manufacturer is lower than the general price approved by the Ministry of Finance, the competent tax authority should examine the related cost and sales data before accepting the declared price. If the manufacturer fails to furnish relevant books or documents, or if the declared price is inconsistent with the data furnished, or is markedly low without due reason, the competent tax authority should determine the taxable value according to the general price approved by the Ministry of Finance.