Structural remodeling.
You should always check with the local office and apply. If the contractor does this first,they will tell you the right answer at the zoning office of the township you are looking to work in.There could be other requirements after the job is explained to the code officer, he might have a question or require additional credentials.Always apply first,for the codes change yearly.
I think it depends what remodeling you would like to do. If is something big or historical then yes.
Depends on the Project, Remodeling, Changing fixtures?
It depends on what your building department requires and what type of changes that you are making. Cosmetic changes don’t usually require a permit but some counties may require it so it is always good to check.