The prices of the same and different calligraphy are different in different people's eyes, but no matter whose calligraphy and painting are good or bad, there are valuable and worthless, expensive and relatively cheap, so we can't talk about it in terms of square feet, we can only say how much a piece is. Runge has no definite aim, but is just a reference, which mainly depends on his own judgment and understanding of his paintings and calligraphy, as well as the speculation in the market at that time. The price of a calligraphy and painting will be different in different places, different times and different auctioneers. So it is difficult to judge, and it is not an absolute price; Besides, any personal evaluation is only one-sided and personal. Features, celebrities, and people who like them in particular may make the price higher. However, if the price of painting and calligraphy is high only because someone has a job now, or simply because of hype; Then when he retires, or no one speculates, the price will soon come down, even worthless. This is true of any other work of art. As long as it's okay, it's collectible. What's special here is that Runge is an unreliable reference, mainly depending on the market and my own understanding of the works, as I said above. Sorry, I can only say so much. I still have to take my own ideas. What others say can only be used as reference. My own opinion, please forgive me for being wrong.
If you want to know more about calligraphy, you can visit Yachang Gallery.