Which books have high collection value?

First of all, thread-bound books, especially those in the Song Dynasty, are basically unavailable in the market, so they are very valuable in the Ming Dynasty. What was printed in the Republic of China depends on whether it was written by a famous artist or had a title, or was out of print and valuable for collection. Secondly, before 1980, books printed in ink that were not reprinted or rearranged were basically the best books published by Zhonghua Book Company, Shanghai Ancient Books and Jiangsu Ancient Books. Others are similar to picture books, comics, and periodicals, all of which were valuable before 1980. Now some old photos are also very popular. I hope I can help you.