Can you find rARE books at flea markets?

If you go to enough flea markets (or library sales, or church bazaars, or yard sales) and you know what to look for, eventually you will find a rare book or two. Everyone who does it enough has stories of great finds. But MOST rare books were purchased by collectors who knew they were getting a rare book. So most rare books come from previous collectors by way of antiquarian book dealers or auctions. The best source for buying rare books is through a member of a national or international trade organization of booksellers, such as the International League of Antiquarian Booksellers (ILAB). While you may find good books and good booksellers outside of ILAB, only members of trade organizations can offer guarantees of authenticity and ethics that go beyond their own business.