Have you ever been a vendor/crafter at an outdoor Festival?

How do you know if being a %26#039;vendor%26#039; at local Festivals etc is worth the booth cost? I work for a company that sells designer inspired purses (they are NOT knock-off%26#039;s etc.,) and other accessories. It%26#039;s like in-home parties/open-houses.. only there is only allowed one %26#039;rep%26#039; for a very large area. I was thinking of doing some local festivals, as I%26#039;ve already done an expo and have racks etc to use. At the expo%26#039;s my main goal is to get bookings for parties- not necessarily to sell my products. However I think at the festivals my goal would more be to sell the products! Can anyone give me any advice on how you can figure out if they are worth it? I don%26#039;t want to waste a weekend and $300 dollars (plus i would need to buy a tent/cover canopy) to sell $250 dollars worth of product. The prices average $35 dollars each and we carry wallets, sunglasses, anklets, other jewlery, and Finders Key Purses%26#039;. Any advice is appreciated. Thanks! Or would I do better at a craft fair?