Remember you resume will be read by humans as well as by machines which will scan for the right keywords. So put some time and energy into your keywords when you write. Resumes must grab the attention of both the human and the computer scanner.
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.
A clean clear and attractive template for a resume is appealing showcases the important sections of the resume in a proper way and catches the attention of the readers in a way that they will read all that you have in it rather than reading just a few lines. The more time you gain from a recruiters attention the more are your chances of getting an interview call.
The template of the resume which is actually the outline or the structure of the resume decides the positioning of every element of the resume. If this positioning is clear and clean with an equal weightage given to every element it appears that there is a flow in the format and so the resume appears attractive. Such a resume neither looks like a piece of art which shows that you were keen about the outline of the resume rather than the content nor does it appear as an essay.