This document provides guidance on calculating transaction value (TV) for imports and exports according to customs valuation rules. It states that for imports, the CIF (cost, insurance, freight) value should be considered as the TV, while for exports the FOB (free on board) value should be considered. It outlines the steps for calculating customs duty for imports, and notes that buying commission is excluded from the invoice price while selling commission is included. The document also distinguishes between CIF and FOB values and notes that landing charges should be added to CIF.