In transactions between affiliated companies or persons, or in other circumstances where the relationship between the parties is such that the gross income from the transaction is not indicative of the market value of the subject matter of the transaction, the Tax Collector shall determine the “market value” upon which the Town Privilege and Use Taxes shall be levied. “Market value” shall correspond as nearly as possible to the gross income from similar transactions of like quality or character by other taxpayers where no common interest exists between the parties, but otherwise under similar circumstances and conditions.