There were many books stacked on the table, and whoever set up a stall and paid for it was recorded on them.
There were many small wooden tablets hanging behind the table. These wooden tablets could be separated in half. The specific location of the stall was written on the wooden tablets. Only half of the tablets could be taken away, and the other half would hang in the store.
"If you don't set up a stall anymore, or if the date of payment is up, you have to bring the wooden plate back and hang it with the other half of the wooden plate. Only when you make sure that you can open up the shop will you be given half of the wooden plate again."