I do a few shows a year( I have learned to pick my shows carefully) . Interesting my last fall show was tied for the second best $$$ in the over twenty years I have been doing them . That show was rightin the midst of three straight weeks of the stock market going down every day) .I just had one show in that last few weeks and for that show it was the highest $$$ for that show in the ten years of doing that particular show.
My biggest advise .. pick your shows carefully. When I first started I was not too careful , nothing is worse than going to a show with a good amount of $$ and time invested in your inventory and coming home with most of it.
My second advise pick what you sell carefully .