On the line I will shoot at least three arrows, and if other shooters are shooting slowly, I will shoot one more as time permits. I have seen fast shooter shoot four or five and slow shooter only shoot three. It doesn’t matter much unless you’re really holding up everyone.
Bring everything you need to shoot but your bow. Most boyers have loner arrows, but hard to have something for ever bow weight and draw length plus have that for more than one person shooting your inventory at the same time. Bring what you know you would need for the bow weights and types you want to shoot. You also want to be able to compare bows to the same arrows you shoot for weight and type. I can tell a lot more about a bow when shooting an arrow I am familiar with shooting all the time.
If I was traveling a long ways and staying a couple days, I would try to have a couple extra arrows along. The distance for shooting is only about 8-10 yd. So you can slap some arrows over a weekend The last thing you want to do is wreck a couple and not have much left to shoot although I am sure a vendor can fix you up with more.
I am local so usually have 8 along with half set up for different spine range to better cover the spectrum of bows I will shoot. Sometimes I mix them to see what a bow likes. At times I will change point weights if needed to get a little closer on tune. It is very short range so it is not like you have to have the perfect flying arrow, but I like to be as close as possible particularly if I am zeroing in on a bow I really like.