Considering the low profits made on LDS books, can you ever break even in royalties to make up for the cost of paying an editor?
Good question. Depends on the book and how well it sells. If you're with a small press, maybe not. If you're with one of the larger publishers, then yes, you can make back your editing costs, plus some.
A friend of mine edits for a mid-list LDS author who has her edit every book before she submits it to her publisher. The author's books are usually around 200-250 pages. My friend charges her by the hour, rather than the page and it's usually around $150. I don't know what the author's book sales average, but she keeps coming back to my friend so I assume it's worth it to her.