If you don't need a major overhaul, you will be quoted an hourly editing fee. (oregonresumes.com)
Again, why would a literary agency work hard to sell your manuscript when it's much easier to collect editing fees from unsuspecting authors? (literary-agents.com)
You should start putting some money aside for editing fees whilst you're still writing your first draft (preferably tuck it into an interest - earning account!). (thewritelife.com)