A purchase permit is a permit that allows you to buy a handgun and is issued by the Law Enforcement in each county. An application is filled out, a fee paid, and the Sheriff or police department does a background check except no fingerprints are taken. After a waiting period, you can pick up the permit from the Sheriff. You take that permit to the dealer that you are buying the handgun from. It is proof that you meet the federal requirements of not being a convicted felon, not a fugitive from justice, or have not been declared mentally incompetent.
The permit is only good for North Carolina residents. It is against federal law to buy a gun out of state unless you have a Federal Firearms Dealers License. The purchase can be arranged and even paid for, but the transfer to another state must be through a federally licensed firearms dealer (FFL Dealer) in the state of your residence. You in turn then get the gun from the FFL dealer in your state. A non-resident cannot get a purchase permit in NC.