Is Cui Shibo's handwriting 300 expensive?

No, it's probably 1000+ on the Internet.

Cui Shibo: Male, 42 years old, majoring in Chinese, graduated from the advanced course of the training center of China Calligraphers Association in 2005, and is a distinguished calligrapher in Jiangsu Academy of Traditional Chinese Painting. Selected Works: Lin Sanzhi Prize of the First Nanjing Calligraphy Media Triennial Exhibition.