An authority shall consist of five housing commissioners appointed by the county commission, and the county commission shall designate the first chairman. None of the housing commissioners may be county officials or county employees. The housing commissioners who are first appointed shall be designated by the county commission to serve for terms of one, two, three, four, and five years, respectively, from the date of their appointment. Thereafter, the term of office shall be five years. A housing commissioner shall hold office until his successor has been appointed and has qualified. Vacancies shall be filled for the unexpired term. Three housing commissioners shall constitute a quorum. The county commission shall record a certificate of the appointment or reappointment of any housing commissioner and such certificate shall be conclusive evidence of the due and proper appointment of such housing commissioner. A housing commissioner shall receive no compensation for his services, but he shall be entitled to the necessary expenses including traveling expenses incurred in the discharge of his duties. When the office of the first chairman of the authority becomes vacant, the authority shall select a chairman from among its members. An authority shall select from among its members a vice-chairman, and it may employ a secretary, who shall be executive director, technical experts, attorneys, and such other officers, agents and employees, permanent and temporary, as it may require, and shall determine their qualifications, duties, and compensation; except, that none of them shall be a county, state, or municipal officer or employee, nor a partner of such, and none of them shall be, or have been for three years last past, a housing commissioner, nor the partner of a housing commissioner. An authority may delegate to one or more of its agents or employees such power or duties as it may deem proper.