A number of books were written in the Roman antiquity, and I would like to understand how they came to be. This question does not concern Latin language directly, but a technical aspect related to its history.
Consider an author who writes a book in ancient Rome. What happens after the writing process is over and the book needs to be copied and sold? Who would have copies made and sell them? Would the author be expected to invest their own money and also get any profits to themselves? Would the costs be covered by a wealthy supporter (such as Maecenas) who would keep the profits but reward the author somehow? Were there publishing companies specializing in this process? Or was it something else?