The commissioner may revoke, suspend, refuse to issue or renew, or place conditions upon the renewal of any certificate issued pursuant to sections 20-417a to 20-417j, inclusive, or place a registrant on probation or issue a letter of reprimand after notice and hearing in accordance with the provisions of chapter 54 concerning contested cases if it is shown that the holder of such certificate has: (1) Failed to comply with any provision of sections 20-417a to 20-417j, inclusive, or any regulation adopted pursuant to said sections; (2) obtained the certificate through fraud or misrepresentation; (3) engaged in conduct of a character likely to mislead, deceive or defraud the public or the commissioner; (4) engaged in any untruthful or misleading advertising; (5) failed to reimburse the New Home Construction Guaranty Fund established pursuant to section 20-417i for any moneys paid to a consumer pursuant to said section; (6) engaged in an unfair or deceptive business practice under subsection (a) of section 42-110b; (7) failed to timely complete any task, as specified in a written contract of sale; (8) failed to remedy any violation of any provision of sections 47-116 to 47-121, inclusive, or any regulation adopted pursuant to said sections; (9) failed to remedy any violation of any provision of the State Building Code; or (10) if applicable, failed to maintain its certificate of good standing issued by the office of the Secretary of the State.