To distinguish the good resume writing services from the bad ones you need to find out how they proceed with the task. A good service asks you to fill out an online question. They also set you up for an interview with the writer. This ensures that the writer is aware of all details that must be present in your resume. If a personal interview is not possible they may also provide you with other ways to get in touch with the writer.
Functional resumes are good when you have little to zero work experience (or new grads). This type of resume allows you to showcase skills that fit in with the job requirements. Fair warning: most recruiters and hiring managers dont like this format and feel as though you may be hiding something. If you have a chronological resume you do not want to have one part chronological and one part functional because it will throw off the entire formatting and may confuse the employer about your skill set.
Were not sure where they came from but the generic objective statement... Im seeking a position with a growing company blah blah blah is out. Today those in resume writing services know that objective statements scream out of date. Using them tells HR professionals and hiring managers that you arent staying current in the latest career trends and by default that you arent staying up-to-date in anything else.
Focus on achievements Employers not only want to know what you have done in the past they also want to know where you have excelled. If you have awards achievements or on the job highlights make sure to add them. If you were part of a team you were part of the success. If your project increased production by 20% and you played a part in it add it on your resume!
The next thing you need to do to get a searchable job-winning resume is to incorporate keywords. Resume services can help you best weave keywords throughout your overall piece. Otherwise you can match up keywords from the job ad and integrate them into your resume. Using a core competencies section in your resume writing where you list out keyword phrases is also a good idea.