Have to be there early the days there are open (Thursdays and Sundays) maybe need a selling permit of the city. Check in to that, and then you get charged for the spot or spots you use to sale your items. The people that you need to pay to use the spots will walk up to your space and then you pay them.
I'm agreeing with Lawrence...get there early. Around 6 am maybe. Go to the building where they make breakfasts.
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