Which of the nine valleys in Japan has the most valuable signature?

As far as I know, the most valuable signboard of "Jiugu" in Japan is "Jiugu Zhuangsan". Therefore, the porcelain of Jiugu "Jiugu Zhuangsan" is more expensive. However, please note that the value of art collection will be affected by many factors, including but not limited to the quality, historical value, rarity and market demand of works. Therefore, if you are considering buying Jiugu's works, I suggest you fully understand the relevant market information or consult professionals.