Editors are Angels:
You may feel an editor is important before you send anything out. They are terrific. No question. However, I blithely thought editors were those wonderous ethereal beings that sorted out the wood from the chaff and polished novels into shiny diamonds without having to lift a finger.
No, not true.
Yes, of course editors are amazing. Adroit, skilled, clever and everything else in that line. They will communicate with you. They will check you are happy before moving on, and, from what I understand, will offer a variety of suggestions. All very useful.
If you feel an editor would be helpful, then go for it.
Whether or not you are paying for their service directly, you should expect clear guidance and honesty. They should tell you how they can be of service, and help to tidy your work up, or be candid and tell you it’s not their bag. If that’s the case, you will simply need to find someone else.
If you want a ghost writer, that’s an entirely different story. I don’t know anything about ghost writers, but I guess they take the hard work out of writing.