You can use the Shenzhen Bank of Communications credit card to buy things in Hong Kong, as long as you have a credit limit, and there are no handling fees. If you feel the quota is not enough, you can apply for a temporary quota.

To apply for a temporary credit limit, the cardholder must have held the card for at least three months to apply for a temporary credit limit. The cardholder must call the bank's customer service to apply. The bank will make adjustments based on the customer's credit status and card usage.

The temporary credit limit is valid for up to 3 months. After expiration, your credit limit will be automatically restored to the original limit. After the temporary limit expires, the used temporary limit (the portion exceeding the fixed limit) does not enjoy the revolving credit facility and will be included in the minimum payment amount of the latest bill and must be paid off in one lump sum on the due payment date.