Editors usually charge by the word. I think I read something like .015 per word... if I can find the site, I'll send you the link. Count the number of words per page and figure it out. At first sight, the rate does not look bad.
I have 185K words so far. Let's see, .015 x 185,000 = $2,775.00! I had no idea publishing a book would be so expensive! Maybe I picked the wrong hobby!