I want to buy an ancient book collection. Is there a recommended place?

Buy enough internet cafes. The Yahoo section of this website has survived from ancient books. There are really many cultural relics that flowed into Japan from the Tang Dynasty to the Republic of China. If you don't believe it, you can buy enough Yahoo online! There are many coal stoves (Japanese second-hand shopping websites), but you'd better ask the customer service before buying them, because the customs of books are stricter recently. Don't ask me how I know. If you didn't buy a book, forget it.