Perhaps there is some misunderstanding of the phrase ‘developmental editing’ used in this article. Given the number of hours necessary to process, dissect, and reconstruct a text of that size, it sounds like anyone who charged that lowly is doing the job for fun and has a spouse to provide for them–all the while devaluing the work of people who do this for a living. It’s really not ethical.
I like the idea of embedding “fine print” into the initial email. I also think it’s a good idea for an author to check references; the questions Val suggested are great. Third, as another commenter said, an editor can give the author a general assessment of their book, which will help the author decide if that particular editor will be a good fit or not.
Obviously there is a big difference. I actually started with screenplays (with some mild success) partly due to hearing that as long as you have a good story, the grammatical errors won’t be a big deal. Well, that was not true. Maybe if a producer liked the story or I was already established but every contest I entered always came back with feedback about the grammatical errors. Even if I won or placed as a finalist, I always received critique on that. Very little is spelling error, it was more about structure, etc.