The auction announcement of an auction company usually provides detailed information about the art to be auctioned, including the name, author, creation year, size, material, valuation, auction results, etc. You can learn about the auction market of Fen's calligraphy works in Qing Dynasty by consulting the auction company's website or related art market analysis articles.
In addition, you can consult professionals in the field of art investment or collection through social media or professional forums to obtain more accurate market information.