If you just want to read it to kill time, you can buy popular books on the market or online paperbacks. The price is cheap, a set of 30-50, which is enough for you to read casually.
If you want to put it on the bookshelf, it is recommended to buy the leather hardcover book bought online. The large leather hardcover book looks good on the shelf and the price is acceptable. When there is activity, it is 100-200.
If you want to read the collection intensively, I recommend my personal collection, the Juzhen edition of the four classical novels published by Zhonghua Book Company. A set of eight hardcover books, with book boxes, beautifully bound and clearly typeset, in which A Dream of Red Mansions was proofread by Mr. Cheng Jia of Qi Gong, and the other three were original classic reviews. Reading and collecting are both good versions.
More advanced for research. Generally speaking, photocopies are used for research. This kind is made by directly photocopying the original, retaining the details of the original. The price is very expensive. Generally, a book 1 1,000-3,000 yuan is generally used for research and is meaningless to ordinary readers.