Buying so many things from abroad is never a great idea -- but there are moments where travelers just need to get so much intentionally especially if one considers it only a once-in-a-lifetime visit. Most travelers have a choice to have a shipping company deliver it to their home address for convenience or they can choose to have it considered as luggage -- which is a clearly impractical choice. Regardless of choice, travelers must know these five things to pay custom duties.

The customs in each airport would tally and total the number of items a traveler has brought home from their trip. Americans are allowed up to $800 worth of items free of having to pay duty, says Independent Traveler. The travel tips website suggests if travelers chose to have a shipper do the honors for their packages from abroad, they only have $200 as a leeway before they pay duty.

According to the US Customs And Border Patrol, the Harmonized Tariff System is the customs "bible" when it comes to categorizing items that are duty-free or heavy on tariffs. As current trade rules will apply on the tariff rates imposed on imported products, items from Mexico could be more expensive to bring into America while Israeli products may be cheaper.

The US International Trade Commission has a tool that helps determine the amount travelers could possibly pay for duty for particular items and products. The Tariff Database takes into account the Harmonized Tariff System and current pricing with presumably regular updates. But this tool is only for estimation and the final amount is still subject to the Customs and Border Patrol's final decision.

To expound more on tariffs: the definition of a levy or toll on the entry of an item depending on existing trade rules with originating country. There is no way to bypass this for regular travelers -- but some importers and shipping companies have arrangements that subsidize their profits with the government. The latter makes for cheaper international shipping due to possibly lower tariff.

When dealing with international shippers, travelers are advised to take on a shipping insurance and pay in credit -- not with cash. Having a paper trail and ensuring your goods arrive in good condition -- this being the responsibility the shipper must uphold which the insurance reinforces -- makes the shipping and passing into customs for duty evaluation faster.