I don't know anything about the flea market, but I know the lighthouse in St. Augustine is haunted as hell. Anyone who doesn't believe in God or the paranormal should drop by and ask about it. I used to live in Florida years ago and the lighthouse is well known. You can be in there alone (or so you think) and then you'll see a moving shadow. Looks just like a person, 3D and everything, but it's blacker than the shadows. You can also hear voices...very distinct voices too. Sometimes you can hear individual words though the gist is difficult to piece. Sometimes it's a man's voice, other times it's a woman's voice. Looking up, you can sometimes see a head sticking down and looking at you, but when you get to the top, there's no one there and nowhere to go!
There's also lots of cold spots. Go by the visitor's center and ask. The guides won't go in after dark. Don't let it being haunted stop you from going. As was noted by Shirley Jackson in The Haunting of Hill House, not every day is Halloween.
As for the JW booth at the market, is it a flea market or a flee market? Ha...couldn't resist.