By at the beach, I mean right across the road from the ocean bay,
between jacksonville & wilmington, nc. . . ."salt areas"

There are a number of salt-tolerant native plants he
http://www.nps.gov/plants/pubs/chesapeake/index.htm
I would assume the ones which particularly can handle the salt spray
would be in sections like this:
http://www.nps.gov/plants/pubs/chesa...half.htm#dunes

This was written for Norfolk, VA and north, but there probably is
significant overlap with North Carolina.

Do you know just how salty the soil/air is? Is there a salty water
table or are they above the water table? Does the wind blow towards
their yard from salt water? I don't have much firsthand experience
with being that close to the coast, though, so I'm just trying to
think of what kinds of questions I'd ask.