this comes up a few times a year..
Depends..
Most will start with a tackle box or old tool box, then grow it to the size of a small armoire with everything under the sun packing into it. They'll then pare it down to something a little more manageable, or into a case for LPR, a case for MPR, and a case for HPR. Some people start off with a tool box full of tool, and soon realize the socket set really isn't needed. And will have a case of motors, then only fly 4 or 5 motors (of the 75 in the case). And all their chutes, and... Plan accordingly, prep the night before, and you only need bring a small box.
Remember, you can always borrow the odd tool. Bring the tools you need for your flights of the day.
I have a modest tote, with a Plano "fishing" type organizer with tools & bits in it. the Tote has chutes, wadding, larger tool, the cases I'll use that day (or pre-assembled motors) masking tape, etc.. Things I typically use in a day, for the flights I have planned. I have a much larger tote at home that has all my rocketry stuff. I pick & choose the bits I want for that particular day flying..
Other flyers at our field have a small-ish tool box & small ammo case for their motors.. A folding table & chair.. that's about it..