Appreciation can be high or low, and collection can be high or low. Whether works of art can appreciate and how much space you can earn mainly depends on whether the object you choose is right or wrong. Don't listen to the people who sell your things brag about the future price, it's just an unknown number! Just like everyone buying stocks, they all hold the mentality of making big money, and no one wants to lose money. In the final analysis, there is still a chance to lose and gain. So we must know something about the collection, don't buy it blindly, and regret it after buying it.
Calligraphy is a very profound art, and there are too many people who can write now. Being able to write doesn't mean being a calligrapher. The most basic thing is to become a member of China Calligraphers Association. How much can it prove that you have a writing foundation (but the members are also nominal), and is there any appreciation potential? It depends on whether he works in a regular art college in China, the usual exhibitions, auctions and gallery prices. Whether the publication is official or not.
Check the reputation of the painter: (xx price) (gallery xx) (xx gallery price) The more pages, the better.