The term “motor vehicle in livery service” includes every motor vehicle used by any person, association, limited liability company or corporation which represents itself to be in the business of transporting passengers for hire, except (1) any motor bus and any taxicab operated under a certificate of public convenience and necessity issued by the Department of Transportation, (2) any school bus, as defined in § 14-275, or student transportation vehicle, as defined in § 14-212, when used for the transportation of children under the age of twenty-one years, (3) any school bus, as defined in § 14-275, when used for the transportation of passengers (A) by virtue of a contract with any public or private institution of higher education, (B) pursuant to a contract for service to a special event held at a location or facility which is not open for business on a daily basis throughout the year, not to exceed a period of ten days, or (C) pursuant to a contract with a municipality for which the carrier provides school transportation service, (4) any motor vehicle operated by or through a community-based regional transportation system for the elderly established pursuant to section 55 of public act 05-280*, (5) any motor vehicle operated by or through a community-based regional transportation system for the visually impaired, and (6) any transportation network company vehicle, as defined in § 13b-116.