Suppose you're a first-time author planning to publish a book independently. In that case, it might feel daunting to find an editor who is professional, affordable and the right fit for your manuscript. A helpful first step is to search book editing services online and read the websites that come up. They'll help you get a feel for the various service levels available and what they include. Most quality editors don't publish their prices online because no two books and authors are alike, and there is variation, but it shouldn't take more than a phone call or email to receive a ballpark estimate.
It's a relatively common practice for editors to review a few sample pages for a modest fee to assess your manuscript and give you a more precise price quote. The sample edit is valuable to both you and the editor – it lets you see the kind of editing they suggest, and it enables them to assess your manuscript and recommend what it needs. It's also not unusual to have more than one editor do a sample edit. It allows you to compare prices and the level of work each one proposes and will do if hired. Authors need to have trust and a comfort level with an editor, which is true in reverse.
When you've settled on an editor and are negotiating the final work agreement, you can ask about any additional services they may provide. For example, some will write book summaries that many authors dread and descriptions for online booksellers and general promotional copy. Because your editor has worked closely on the manuscript, they learn a lot about the book and are well-positioned to summarize it and help with promotional wording. Unless it is cost-prohibitive, it is wise to sign up for the service level recommended by the editor you choose – they have your best interests at heart.
If you're not yet sold on the value of professional book editing, look at it from your readers' perspective. They are intelligent, and their expectations are high. You need to provide an engaging, readable book on par with those released by the world's most respected publishers. If you publish anything less than that, you'll likely feel regrets in the long run and hurt your chances of writing more books in the future. The internet keeps things alive for many years, and it will always be easy for people to find out about your first book, reviews, and all. The best professional book editing is a major asset to authors.