The first step in choosing the best antique Chinese porcelain is to get knowledgeable on the topic. There are unfortunately many fakes and reproductions flooding the market, and the more you know about antique porcelain the more discerning you will be able to be. It is advisable to read informative books and articles on Chinese porcelain, to view a variety of specimens in museums, antique shops, auctions and online sources, and to talk to knowledgeable antique dealers and other collectors.
You will need to learn about the kinds of Chinese porcelains that were produced in the Qin, Han, Sui, Tang, Song, Yuan, Ming and Qing imperial dynasties, and about how to recognize porcelain marks, designs and patterns that were prevalent during a particular era. Amongst other details, it will help to learn about the types of glazes and pastes that were used, the colors and shapes that were in fashion, and the types of imperial marks that were used to stamp the porcelain. By acquainting yourself with the production materials and methods that were used in ancient times, it may become easier to tell an antique Chinese porcelain piece from a more modern reproduction.
Once you've become reasonably knowledge on the subject, you can check out various offline and online sources for purchasing antique Chinese porcelain. It is necessary to keep in mind that genuine antique porcelain objects, being rare and often exquisite, are priced quite high, and will not usually be found on low-priced auction sites. It will be a good idea to buy only from a knowledgeable seller or dealer, and to have a piece examined by a third-party expert before final purchase. If you are buying from an online source, ask to see several clear photographs of the piece and a condition report, and ask for a written guarantee that allows you to return the piece for a full refund if the item is not up to par.
Some dealers offer a certificate of authenticity or provenance, but, while these can be useful to an extent, they are not always completely reliable. It is not always possible for a dealer to know the entire, exact history of an antique Chinese porcelain item. You need to be wary of objects that purport to have a valuation from a museum, as museums are not allowed to make such valuations or appraisals.
If you are buying antique Chinese porcelain from overseas, you will need to familiarize yourself with the customs rules and regulations of both that country and your own. Some countries disallow the export of antiques, while others may charge a certain import duty. You will need to have the proper purchase papers detailing the objects to be genuinely antique.