How to apply work visa hong kong and how much price ?

Hi, you should first prepare those documents including copy of passport, a completed application form, a recently-taken passport-style photo, work experience and schooling certificate, and copy of the alien employment permit. Your employer needs to provide the application form, copy of the contract, business certificate, copy of the financial support, and introduction letter of the company. Then, submit the application to Chinese embassy or post it to HK immigration department directly.
Address: Receipt and Despatch Sub-unit
HK Immigration Department
2/F, Immigration Tower
7 Gloucester Road
Wan Chai, HK
It may cost $ 190 if you submit the application to HK. Just for reference.