Not all fairs are the same. You need to find out what people normally buy at this fair. What price ranges, subject matter, styles, etc are people going to be shopping for.
It's to these standards that you want to pick your products from, not what you think is your best, not what you'd like to sell, but plain what are people buying criteria.
If your originals are too expensive for the fair goer than sell cards, pillows, t-shirts, etc with your art on it. Be creative with how you use your art to sell it, not just in creating the original.
Have cards and brochures to hand out with your FAA store and other where to buy info. And make these interesting reading not just a sales catalog.
I would recommend having no more inventory than what you need to make a pretty display (not what you hope to sell). You want people to pick through this stuff first and buy it, even if they would have chosen something else if had total selection. If they want something other than what you've already paid to have printed they can order it online. Otherwise, then you can make them happy by saving them the hassle. You want to sell your display, not pack it up for the next one. Having everything people like isn't the same as what they will buy. You can't afford to carry the inventory cost of what everyone likes and you need to guess right on what will sell.
-- mary ellen anderson