Probably not the thread to say this, but if you are in North Carolina, I highly suggest that you call them the correct species, Cope's gray tree frog, and even though there are a few tiny populations of Hyla Versicolor, (Common gray) the two species are told apart by their calls, which you have said you heard some calling. Just don't call them "American gray tree frogs" and do research on distinguishing the two species and sell them as such