Flathead, Lake, Lincoln, and Sanders all have planning and zoning departments. (This is a State requirement.) However none of them have building departments. So outside of any incorporated cities, the only permits you will need are for electrical, plumbing, and mechanical work. (Also a State requirement.) The Flathead County Geographic Information System (GIS) at https://flathead.mt.gov/gis/ provides a wealth of information from soil series to election districts. The Montana Cadastral System at http://svc.mt.gov/msl/mtcadastral/ provides property records for the entire state. Point being is that any restrictions largely depend on the property not on the county.