If you can't edit, you can't write well, either. Editors are good things, but a good editor never rewrites anything, ever. A real editor's job is simply to help make teh book better by suggesting this change or that change, which the writer has to implement.
Stop making me agree with you!
Betas/friends etc are not the same as an in house editor is not the same as an editor you hire
Betas/friends will point out plot holes/continuity problems/clunky phrases. Editors you pay will do the same on a more professional level (and are essential if you are self publishing -- though anyone charging as little as $100....I would winder how good they are tbh)
An in-house editor is not just thinking about your book -- they are thinking about far more than that -- how this book will fit in with what the imprint wants, for example. Their copy editor will have house style to implement (and it may grate -- apparently using ; and : in dialogue has now become a thing with my publishers and I just can't....fingers...chalkboard....)
"Editing" covers a HELL of a broad reach. If you hire one, and there are pros and cons if you are doing so before subbing to agents/editors, you need to be specific in what you want/need.