The new restrictions range from higher tariffs to costly import licences and customs controls.

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If you are looking to understand what your competitors are shipping, you can check out a company like Manifest Journals where a business connection of mine, Michael Heffernan, helps companies make sense of U.S. Customs Import Trade Data.

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Import quotas have largely been replaced with customs duties, and subsidies, tax breaks and other special favours for farmers scaled back.

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In January customs officials stopped letting Nordenwagen import Porsches.

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On the one hand, it created a much larger audience for modern art and even led to a change in American customs laws making contemporary art easier to import.

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If this limit is breached, HM Revenue and Customs can insist on the payment of import duty and VAT of up to 20% on many items, which may include those prized jeans or iPods.

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And when the center supplied computers to various teams, some got stuck in customs because no one had checked up on import duties.

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On the import side, Argentina cannot raise tariffs on its own because it belongs to the Mercosur customs union.

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Chinese garlic would be declared, at import, as originating in countries with whom the EU has preferential arrangements in place, where normal customs duty do not apply.

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