The cost is about 10000 to 30000 yuan. According to Article 20 of the Rules for Certification of Seafarers' Competency Examination in People's Republic of China (PRC) (2020), if the certificate of competency expires for more than 3 months and less than 5 years, it shall participate in simulator training and knowledge updating training, and pass the corresponding spot check evaluation; If the certificate of competency expires for more than 5 years 10 years, it shall participate in simulator training and knowledge updating training, and pass the theoretical examination and project evaluation of the corresponding spot check subjects; /kloc-personnel who have expired for 0/0 years or more shall participate in simulator training and knowledge updating training, pass the theoretical examination and project evaluation of corresponding spot-check subjects, and complete the on-board internship for not less than 3 months within the corresponding navigation area and grade range recorded in the competency certificate in accordance with the provisions of the Record Book of on-board Internship. The cost is still a little high.