Im not entirely sure but my guess would be 10 or more. Your best bet would be to call and ask or message them on facebook :)
For maze 10 or more is $6 person. 30 plus is $5 per person. Christine is correct on that is when one person pays for group so we do not go through one hundred $1 bills making change for everyone in a group.
I think our group was 6 people. Be ready to pay in one transaction.
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