Resume preparation services are common and easy to find, and though I've never used such services I am sure many people do and I would not view it as unethical as long as the resume accurately summarized experience and qualifications.

Many college hires will use their college's resume writing workshop, and there are also commercial options.

Also, friends and family.

Why wouldn't you get the single most important document in the application process reviewed and rewritten?

I hope it was carbon black ink on papyrus ))