We pulled into Topsail Island late on Sunday afternoon. No one came up on the radio so I phoned the marina and got Captain James at his house. He said there was no one working at the marina but he gave me detailed instructions on how to navigate the entrance channel, which wasn't difficult. He also said to pick any open slip, which I did. It's not a big place - I'd estimate there are 20 or 25 slips, all floating docks that look new. Another transient boater helped us tie up, and water & electric were obvious, so no problem there. The only problem was that we never did see anyone who worked for Topsail Island Marina, and we didn't know where the bath house or trash bins were...and we never did find them. The Wifi didn't work, but Captain James told me it's because the cable was cut at the road, where there was construction. Entrance and departure were easy, although if you're southbound you have to leave just before the top of the hour, because the marina is right next to the swing bridge and it only opens on the hour.
I would stay in this well maintained, totally protected little marina, but I'd be more careful to ask for details as to the amenities.