Feng Jiquan, the word Xiaoyin, is from Guiyang, Guizhou, and a calligrapher in China. Contemporary calligraphers are local calligraphers, so the price of their works will not exceed that of 300 yuan. There should be something wrong with the size of your target (50X2000). You can measure the size of the work, square meters times 0.9, and the result is square feet, and square feet times 300 is the market price of the work.
For reference only.