There will be costs. First of all, from grading to evaluation, it is necessary to invite a third-party evaluation agency to conduct evaluation, and the evaluation fee is required; Secondly, if there are many places that need rectification, it may be necessary to add some equipment; As for filing, supervision and inspection, there is no charge
Level 3 should be evaluated once a day, which means the validity period is 1 year, so don't worry after the first time.