Yes. In the interest of providing for inexpensive housing options for family members as well as for neighborhood protection, Walton County has established various Accessory Dwelling Unit requirements. Section 2.02.00(B)(3) of the Land Development Code provides the general restrictions on accessory dwelling units. Some Neighborhood Plan Areas also establish ADU requirements and restrictions, notably the Inlet Beach Neighborhood Plan.
To summarize the general Code requirements here, small accessory dwelling units less than 800 square feet in size, are allowed in all zoning districts that allow residential development. They cannot be used as short term vacation rentals separate from the primary residence and they must not detract from the single-family residential character of a property. This means essentially, that they need to be designed in way that is ancillary and compatible with the primary structure and that does not detract from then neighborhood.