I am going to worlds this year, and I was wondering how much money you all think I will need to buy stuff from the booths? Please help!
As much as your willing to spend. 
that depends highly on your level of self-control.
As much as you can/ want to spend on yoyos!!!
last year I brought umm… I think $400? I left with a good amount of stuff though. haha (pinnacle, jirorian, pacquiao, big yo, go big, raptor, BK (top), fiesta xx, 2 werrd shirts, 2 pairs of jimmy hats, and a bearingized CW)
I think that’s everything, but I might be forgetting some.
point being, it depends one a) how much you can spend, b) how much you’re willing to spend, c) level of self control
I blew my whole vacation fund on yoyos basically, so I had to skip out on universal studios. Well worth it though.
I would recommend checking around a bit though. I bought a jirorian for $110 from the… umm I don’t actually remember who it was, one of the main booths. When it turns out I could have gotten one for $65 from someone else.
Some of the stuff there though is highly discounted. Like werrd was selling rozzors and rozzor 2s for $50. YYJ had go bigs for $25, etc.
Worst case scenario if you bring too little, go out into the hall right outside the ballroom and there’s an ATM right there. It has I think a $2.50 charge to use it though.
Which reminds me, bring cash. A lot of the booths don’t accept credit card.