(a) In determining cost to the wholesaler and cost to the retailer, the court shall receive, and consider as bearing on the bona fides of the cost, evidence tending to show that any person complained against under any of the provisions of this subchapter purchased the cigarettes involved in the complaint before the court at a fictitious price or upon terms or in such manner or under such invoices as to conceal the true cost, discounts, or terms of purchase, and shall also receive and consider as bearing on the bona fides of the costs, evidence of the normal, customary, and prevailing terms and discounts in connection with other sales of a similar nature in the trade area or state.
(b) Where a cost survey pursuant to recognized statistical and cost accounting practices has been made for the trading area in which a violation of this subchapter is committed or charged to determine and establish on the basis of actual existing conditions the lowest cost to wholesalers or the lowest cost to retailers within the area, the cost survey shall be deemed competent evidence in any action or proceeding under this subchapter as tending to prove actual cost to the wholesaler or actual cost to the retailer complained against, but any party against whom any such cost survey may be introduced in evidence shall have the right to offer evidence tending to prove any inaccuracy of the cost survey or any state of facts which would impair its probative value.