The invoice should itemize labor costs, parts supplied by the foreign repairer, and any overhead charges, clearly distinguishing the repair value from the pre-existing value of the article. CBP may request the original purchase invoice for the article to benchmark the repair cost as a plausible fraction of the article's total value. Vague or lump-sum repair invoices are a common trigger for CBP examination and potential reappraisement.

Warranty repairs are specifically excluded from heading 9802 (which covers non-warranty repairs and alterations) but may still be entered under 9801100000 if the article was previously imported and the repair value is dutiable. However, some warranty repair scenarios may qualify for duty-free treatment under other provisions depending on the circumstances. Importers should review the specific facts with a licensed customs broker before filing, as the distinction between warranty and non-warranty treatment has duty implications.