Lots of good writing stuff out there in cyberspace today! Here's another re-post.
Literary agent Nathan Bransford shares his take on hiring freelance editors to look over your project before submitting.
When I was getting ready to submit Final Approach, I had the benefit of wonderful critique partners. But I also had low self-esteem as a novelist. Final Approach was my first try at fiction and my educational and professional background was in engineering and science. No MFA or short story credits in sight.
I did hire an editor and I'd make the same choice again. Like Nathan says in his post, I found a vetted person for the job--a multi-published author with years of editing experience for a small press. Really what I wanted to find out was whether he thought the manuscript was viable. (Or did it sound like it was written by a third-grader?) He addressed some plot issues and cleaned up copy-editing (a bonus), then told me to get busy writing another book. For me, the value of my freelance editor was as much in his mentorship as in his editing. Two years later, he still checks on me from time to time.
Everybody has a different experience to share, but since mine was so positive, I do think that if you can afford it and know what you expect to get from it, that there is much to learn from an editor.