Customs valuation hierarchy: transaction value with objective adjustments, then identical/similar, deductive, computed and residual methods. These Rules set a hierarchical customs valuation method with the transaction value (adjusted as provided) as primary, subject to conditions on restrictions, determinable sale conditions and related-party influence. Where transaction value is unacceptable or cannot be determined, the Rules require sequential application of transaction values of identical or similar goods, deductive value, computed value, and a residual method. Rule 10 prescribes specific additions to price (commissions, packing, buyer-supplied elements, royalties, proceeds of resale and other conditional payments) which must be objectively and quantifiably established; importers must declare value and provide documentation, and the proper officer may reject declared values after inquiry.