Our pricing is based upon the assumption that what we're receiving is a clean, fully-edited manuscript--a final book. However, over the course of the years, we've found that fully 97.8% of our clients copy-edit after we've returned the ePUB to them for review (please see our What's the Process? article--we mean Step 6). Now, some companies include a certain amount of editing "time" in their initial quotes--say, an hour or two.
But we don't believe that the clients who don't have 30 minutes of editing should be charged as if they do, so we charge our base price with the assumption that our clients will have 5 copyedits--and we include those 5 for free. (A copyedit is a single edit--one typo, or adding a comma, not an entire revision pass). When we say "copy-edit," we mean changes to the manuscript that were not in the book that we were given to convert, or, edits that have to be made because the manuscript was not cleaned properly by the publisher (for example, broken paragraphs from a scan or a conversion from PDF). We are working in HTML, not Word or some other word-processing program, so copy-edits take far longer to do than they do in Word.
We charge for copyedits after the first five. What this means is that when it comes to edits, each client, essentially, sets the final price of their own book themselves, by how good a job they do with their manuscript clean-up, editing and proofing beforehand. Revisions also affect turnaround time, obviously, as we have to make the edits and return a revised ePUB to you for review and approval. So, just like pricing, you "set" the length of your turnaround time by how clean your manuscript is when you give it to us.
The cleaner your file, the better the price and the faster the service.