I went to the Moss Landing Antique Street Fair in Monterey County, California yesterday. The fair was huge, so I didn't get to see everything, but it was interesting to see so many antiques and collectibles. Before I got there, I wasn't sure how affordable things would be, but not everything was out of my price range. I ended up purchasing an antique pendant, purse, and three vintage pocket watches for great prices.
Prices vary, so it's always good to compare prices before buying unless you already know the value of an item and are sure that you have spotted a good deal. I suggest reading up on the kinds of items you have in mind to get an idea of what you can expect to pay before going to a fair, otherwise it may be difficult to know if the vendor is asking for too high of a price. Then again, you don't want to waver too much while at the fair because by the time you come back for an item, it could be gone! It's also possible to talk some of the vendors into cutting you a better deal. And this may seem obvious to those of you who have been to street fairs before, but make sure you have cash if you plan to buy anything, and don't forget the hat, sunscreen, and comfortable shoes.
The fair has hundreds of booths plus some permanent antique shops, so I recommend it if you are ever able to go. It's held the last Sunday in July annually. Here's a link if you're interested: http://www.mosslandingchamber.com/special_events/street_fair.html.