The price you’re going to pay an editor depends on a lot of different factors. You may just want an editor to proofread your book to catch minor errors and typos. Or you may want to work with an editor to help you overhaul your book. Getting familiar with the kind of editing options available will help you choose the right editor. Typical book editing services are:
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.