Renewing work permit and residency with same teaching company

Is it correct if you intend to renew your teaching contract with the same company you work for already, that it is necessary to get a new criminal record check and have your degrees legalized again or because you received a wok permit last year and were approved by the government bureaus that these requirements do not apply to you, but would apply to new teachers only?
What documents do you actually need to apply to renew both the work permit and residency permits working for and at the same company / school location ? Please advise, thanking you in anticipation. Kind regards.