Fla. Stat. § 938.35
The board of county commissioners or the governing body of a municipality may pursue the collection of any fees, service charges, fines, or costs to which it is entitled which remain unpaid for 90 days or more, or refer the account to a private attorney who is a member in good standing of The Florida Bar or collection agent who is registered and in good standing pursuant to chapter 559. In pursuing the collection of such unpaid financial obligations through a private attorney or collection agent, the board of county commissioners or the governing body of a municipality must determine this is cost-effective and follow applicable procurement practices. The collection fee, including any reasonable attorney's fee, paid to any attorney or collection agent retained by the board of county commissioners or the governing body of a municipality may be added to the balance owed, in an amount not to exceed 40 percent of the amount owed at the time the account is referred to the attorney or agents for collection.
Fla. Stat. § 938.35