1.) A mayor may receive payments from his former firm for work performed for and authorized by the city long before he took office. The contract was authorized long before the mayor took office, and no violation of Section 109, Miss. Const. of 1890, or Section 25-4-105(2), Miss. Code of 1972, will result. Because the work was performed before the mayor took office, the firm is not a contractor to the city, and no violation of Section 25-4-105(3)(a) will result. 2.) If the mayor has a “material financial interest” in the firm, then the mayor's former firm cannot serve as a subcontractor to the city and perform future services, pursuant to Section 25-4-105(3)(a), unless an exception applies.