The major disadvantage is cost. The average full service, professionally prepared resume will cost $100 - $400. Cost is usually dependent on experience, thereby the entry level professional will pay less than the executive. There are some resume writing services that charge less, even under $50. Be wary, as sometimes the cheaper resume services are merely typesetting your resume in a cookie cutter format and spending little time in helping you market your skills.
The other major disadvantage is time. Its a common misconception that a resume writing service will save you time. Often, you will actually spend more time using resume services as the resume writer has not been in your shoes and will require constant communication to ensure they represent you clearly on the resume. The resume writer is going to need to work with you to learn every aspect of your career and that takes time. If you are looking for a service to save you time, then you are taking the wrong perspective.
Another problem is finding a good writer. How do you know whether the writer has the necessary to write your resume? Here are some things to consider when choosing a resume service:
Look to your colleagues for recommendations. You may be surprised to find out how many of your co-workers have used a professional resume writing service.
Look at the writer's credentials. Does the writer specialize in your industry? Does the writer have many years of experience?