Moreover, the casual distinction between a (developmental) “editor” and a “copyeditor” can be a bit simplistic, particularly in a self-publication or even vanity-publishing context. A self-published author may barely have the budget to hire one editor, so that editor needs to be able and willing to blur the lines between developmental editing and copyediting. The editor must also be accustomed to working with authors of a variety of strengths and weaknesses, including many whose work would not, in fact, have been accepted by a commercial publishing house in its current form. I have come to take great satisfaction in taking a new or newish author by the hand and helping them find ways of making their work the best it can be. Of necessity, this must include line-by-line correction of grammar and style (often a surprisingly great amount of such correction), but can rarely be limited to that.
It’s always sensible to follow due diligence in submitting your first draft of your book to an editor by making as fool-proof a copy as possible for you because first, it is your own creation, and secondly, a horrid draft sent your editor can end up frustrating both you and him or her. Make your own corrections to the extent you can, so that will make the job of your editor that much lighter and the end result would be a lot more effective.