A lot of properties around NCSU are cyclical, meaning, they come on the market in the Spring and/or Summer when leases are ending and the owner decides to sell rather than continue to rent. I know the rental climate around NCSU very well. See the link below, The Griffin Realty Group, to set up searches and alerts as per your criteria.
Also, as a division of my real estate agency, I own and operate a Property Management company as well, Nest Property Management. Check us out http://www.nestproperties.net/.
Contact me via email or phone if you'd like to further discuss. Go Pack!