There is created a body corporate and politic to be known as the Georgia Building Authority which shall be deemed to be an instrumentality of the state and a public corporation, and by that name, style, and title the body may contract and be contracted with, implead and be impleaded, and bring and defend actions in all courts. The authority shall consist of the Governor, the state auditor, Lieutenant Governor, Commissioner of Agriculture, and an appointee of the Governor who is not the Attorney General. The authority shall elect one of its members as chairman and a secretary and treasurer who need not necessarily be a member of the authority. Three members of the authority shall constitute a quorum. No vacancy on this authority shall impair the right of the quorum to exercise all the rights and perform all the duties of the authority. The members of the authority shall not be entitled to compensation for their services but shall be entitled to and shall be reimbursed for their actual expenses necessarily incurred in the performance of their duties. The authority shall make rules and regulations for its own government. It shall have perpetual existence. Any change in name or composition of the authority shall in no way affect the vested rights of any person under this article and Article 2 of this chapter nor impair the obligations of any contracts existing under this article and Article 2 of this chapter.