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I am in Japan and I have purchased a kitchen knife (slightly over ¥16,000), claiming back the sales tax. The tax refund office did attach a document to my passport stating the sale.
Tomorrow I will be leaving through Narita. I have read about the procedure and I must show that I am taking the knife away with me. But of course, being it a knife I cannot take it with me in the cabin and I must leave it on the checked luggage.
What will be the proper procedure? May I go through customs before checking in? Or must I declare it when checking it somehow?