No, it doesn't cost money, but you can get a monthly card. One month in summer 15 and one month in winter 10. You can fix your seat, and you can get a card for ten times for ten dollars. If there is no fixed seat, you have to leave.

If you don't want to spend money, you can directly avoid the card checker ~ you can leave when he comes, and you can continue when he leaves, and you can go to any study room on the first floor to the fourth floor ~