2. Processed foods (such as pineapple cake, sun cakes and tea) can be brought in duty-free. However, if it is within a suitable range, the appropriate quantity is that there is no standard, so just don't overdo it. Ten boxes should be no problem.
3。 The same is true for trinkets, just the right amount. Books, as long as they are not repeated, can be brought as personal belongings, but try not to bring CDs, otherwise it is very troublesome to provide genuine copyright certificates and the like.
4. No matter where you change Taiwan dollars, there will be exchange difference losses. You shouldn't be able to change it in the mainland. After checked baggage in Taiwan Province Province, the airport has an exchange counter set up by the bank. Just exchange it there, just like the exchange rate on the island. The ratio of RMB to NT is about 1: 4.8, but it will change according to the foreign exchange quotation of the day. Of course, there is also the difference between buying and selling by banks. In Chinese mainland, UnionPay cards can also be used to withdraw NT dollars from ATMs on the island of Taiwan Province Province, that is, the equipment usage fee will be deducted more (10 RMB), and the exchange rate is the same.
It's much cheaper to buy things in Taiwan Province duty-free shops with NT dollars than in domestic or Hongkong duty-free shops. But this is limited to high-tax products such as tobacco, alcohol and cosmetics. Don't buy any gifts you want to bring at the airport. The airport is nearly 30%-50% more expensive than the island.