New to the Forum and a relatively new spinner. I'm being brave. But ... craft shows - hey - old pro here.
The down side of making hats for sale is folks want to try them on. That is fine, but ... not everyone is hygenic and there is a risk. I know - but felt the need to put it out there. The same is true to a lesser extent for gloves. hand warmers and scarves.
Enough ick. You are competing with machines and acrylics. I don't care what the "artists" say, it's true. You can have beautiful items, but if the average person can't afford them, they will not sell. And people will not tell you that you items are over priced, they will just walk away. Craft shows are not art shows. You should know the difference.
Barter is always good, but you need to figure your yield and your time vs. cash price. Unless you have a vendor turned to friend, and that makes all the difference. You can also take "custom orders" but do get your cost of materials in advance. That way, if something happens, you can sell it elsewhere and take the loss on your labor.
It has to be "cool" weather for wool items to sell. I don't know why no one thinks in advance, but they don't. So save the money on the fees for the summer shows and know you will be working weekends fall and spring.
Lessons learned -- for what it is worth.