This may sound strange, but there no set answer to how much to bring. You have to tailor what you bring to the show you're doing. And the amount you sell always depends on how attractive your display booth is and if the show is one day or more.
It's a simple rule of thumb. The nicer your display, the more you'll sell.
So first a few questions. How big is your space? Is it just for a table, or do you have a set space? Usually at shows you get a 10x10 space and your job is to make it attractive. Also, can you get electricity? Always get power if it's available, even if you have to pay extra. We have a saying that at an indoor show, you cannot have too much lighting. You want the customers to see your work. And they always go into booths that are well lit.
So let me know how big your space is, and we'll take it from there, OK?