There is no handling fee for exchanging foreign currency, but in fact, the handling fee has been included in the price difference of foreign exchange quotations. Especially in the "black market" outside or exchange shops on the streets of Hong Kong, Macao and Taiwan, the "handling fee" is particularly high.

I suggest LZ go to the bank to exchange money.

LZ can exchange foreign currency countless times a day, but Chinese mainland has foreign exchange control, banks have quotas, and different banks have different regulations. LZ has to ask in person. If LZ is in Hong Kong, Macao and Taiwan, it is not restricted.

Besides, if it is illegal to keep changing foreign currencies, aren't all foreign exchange traders going to jail?