I fish the same area with a 2320, if I could trailer a 2520 without getting permits that is what I would have purchased. Can't go wrong with the 2520, I run the 2320 40 miles out in the ocean and all over the bay. If I was going to do it over I would probably get the 25 and take the chance of trailering without permits.
I don't know about the CB area, but in NC I'm not positive but I think you are supposed to get a permit for every trip. I trailered a 25 Bertram with a 10 ft. beam in NC without permits for several years without ever getting checked or measured. Even pulling it on the ferry from Sea Level to Ocracoke and the Hatteras Inlet ferry I was never checked.
My understanding is that if you are not crossing a state line you can trailer the boat anywhere. I guess the best source to answer that question would the the individual state DOT.