Where can I buy Zhang Qian's calligraphy works? About price?

Zhang Qian's paintings and calligraphy are in my gallery. Calligraphy works nave 4 feet, 3500 yuan, buckets, banners, 2000 yuan each. Zhang Qian's 4-foot Chinese painting costs 6,000 yuan, and buckets and banners cost 3,000 yuan each. Demand is greatly reduced. Make sure it's genuine, and ten if it's fake. Xi Labor South Road Datang West City Tang Gallery.