When (what month) do you plan to come to Cape Hatteras?
You can rent a house and stay for not too much $$ in April/May/ very early June.
Then the "high season" sets in and the rents go way up.
You can rent soundfront and sail safely from the front of your house, but it will cost significantly more.
As far as were to sail, if you get a soundfront house or one a few houses back with water access, then you will sail in the sound adjacent to the house.
If you camp, or rent something with no water access, then you can sail at the Canadian Hole between Avon and Buxton. There's a deep water hole just a little ways off shore, but once beyond that the water is knee to waist deep for miles.
There are some nice campgrounds with showers etc. in Avon, and more in Buxton, plus several up the island in Salvo/Waves/Rodanthe.
If you stay up the island there are some launches and a shop up that way as well.
Bring your formula boards, but don't bring your big fins.
The Pamlico Sound is very shallow, and has both sandbars and weeds that make weed fins pretty much mandatory.
The general rule for visiting Hatteras is "bring everything".
It can be dead calm in the morning and blowing 25 knots from the SW/NW/NE in the afternoon. The weather changes alot, but rarely do we get more than a day or 2 of no wind.
It can go to 35-40 knots as well and the temps can change from heavy wetsuits to rash guards and shorts in a 2 day period.
So, bring everything you can and you'll probably still need a weed fin or something. There are plenty of shops here and they have good selections of quality weed fins that work in this area. Pretty good prices also.
Tell me when you are coming down and I can suggest campgrounds and rental house companies.
If you are coming soon, remember that the Frisco Woods Windfest is April 17th-19th this year.
Hope this helps,