Fla. Stat. § 157.05
The work shall be done under the supervision of the committee as hereinbefore provided, and when completed, the committee shall report the same to the board of county commissioners, who shall also inspect such work together with the engineer in charge, and approve the same before final payment is made to the contractor, and the report of said work, together with the approval of the work by the board of county commissioners and the said engineer, shall be entered upon the minutes of the board of county commissioners; provided, that the board of county commissioners may, during the progress of the said work, if they think proper to do so, make payment in installments on said work of not to exceed 80 percent of the value of the work so done, to be certified by the engineer in charge, reporting to the board of county commissioners. Such engineer shall be appointed by said committee subject to the approval of the board of county commissioners.
Fla. Stat. § 157.05