If you just rehab your existing home you don't have to have permission. If you are building on a room addition to an existing home...or doing a tear down re build...you would need to hire someone that can pull the appropriate permits to do to meet the appropriate county/city code.
I may have assumed too much too...but being more specific with your question would be helpful.
All the best,
I only originate in CA, but encourage you to find a local 203K specialist to discuss your options. I would never work remotely on a 203K and suggest you avoid any company/loan consulltant doing this loan from afar. The loan is not difficult, but it has a lot of moving parts...you will want someone you can communicate with effectively.