Fire Department is an independent taxing district, although the sheriff dept is a service provided by the county, the City of Destin pays a contracted price to have more deputies located there. Trash is provided by a private company that charges the residents whether they live in the county or city. Destin Water Users is a private water company providing water and sewer for both the city and unincorporated areas. Just so you are aware SoWal has 3 private water companies that operate, the fire protection is also an independent taxing district, and EMS is also provided by SWFD. Garbage service is paid for by a 1 penny sales tax for the entire county with some caveats that I am not completely familar with. As for the post office, well not sure what that has to do with incorporated or unincorporated areas. Really not a whole lot of differences except we have a mosquito control district.