What is the value of Chang Zhiguo's original calligraphy?

Look at his skill and self-style. If the handwriting is not good, I won't ask him the price. As long as it is good (it must be the calligrapher's own work. It adopts its own style, looks elegant and vulgar without losing the taste of traditional art), no matter how much the price, it must be (art is priceless)