On my opinion for the best price is on the winter and begin of spring.
Victory Beach Vacations has a really good selection and the staff there are some of the nicest people you could ever find!!...they had more than the other rental companies on Carolina Beach, and I've been renting from them for 3 months...they may have the selection you want through the summer, but otherwise I agree with Jason that May and September/ October may be best
May or Sept would be my vote
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