I've done shows that were $25.00 and a couple of 3-day shows that were $600.00. I always do best at the smaller one-day shows, because I know that the lookee-loos who come through and like my stuff will probably be back that day to buy. I tend to do a lot of the high-school shows for a couple of reasons--they are well-attended and well-publicized, and the high-school kids (ROTC, band) are recruited to carry things to and from the booth and car/truck.
There is one 3-day show here in Albq that has run for several years, a week before Thanksgiving--a time when you'd think that people would be looking to spend money on Christmas gifts. The first year we did it, we did pretty good--$1200 in the bank on a $600 investment(without electric). The second year, we put $200 back in the bank on that $600 investment. The "promoter" (and I use that term very loosely) promised a lot of publicity that she didn't deliver, so attendance was lousy, and the people who did show up acted like they were there on a sight-seeing trip rather than a buying trip. I got a lot of "I'll be back tomorrow" people who never returned. One thing we did the first year was to give people a "Be-Back Buck", a little certificate for $1.00 off on a purchase up to $20.00 if and when they brought it back during the show. We got every one of them back.
I also try very hard to stay out of shows where the Avon lady or the Magic Cookware guy is demonstrating.
One of the things we have found in craft shows is that there are very few crafters in the area who work in wood or acrylic. Most of the people at the shows are into fabric crafts or jewelry or pla-do ornaments. We got into one of the high-school shows in December on Wednesday before the show because there were only two other "wood" people registered and NO ONE doing any sort of laser work at all. This is a show in early December that people fight over in June, and we've been pretty much guaranteed a booth at this show for as long as we want, since we aren't doing jewelry, pottery, or fabric crafts.
Nancy