Generally speaking, the value of Gan Long Bao Tong is relatively high, followed by Jiaqing Bao Tong and Daoguang Bao Tong. Copper coins in Qianlong period were very popular at that time, because the economy developed during this period and the coinage industry developed accordingly. Gan Long Bao Tong's casting volume is relatively large, so the value of the rare edition with better appearance may be higher.
The value of Jiaqing Bao Tong is relatively low, partly because after Qianlong, the Qing Dynasty began to decline, and the development of the coinage industry was no longer as prosperous as before. However, some rare versions of Jiaqing Bao Tong may also be of high value.
The value of Daoguang Bao Tong was relatively low, because the economic and political situation of the Qing Dynasty was unstable during this period, and the development of the coinage industry was also affected. But if you are a collector and have a special interest in this kind of ancient coins, then you will look at these ancient coins with special respect and their collection value will increase accordingly.
The specific value also needs to be comprehensively judged according to the specific appearance, preservation state and market supply and demand relationship of coins. If you have specific coins, it is recommended to consult a professional ancient coin collector or institution for evaluation.