Compare and contrast the two legal constructs under which a protective services agent can be employed

This is for my Executive Protection class. You can use your own references. I need 250 words.

Compare and contrast the two legal constructs under which a protective services agent can be employed, ie, “agency” and “independent contractor.” Target is 250 words.

Feel free to use your own references. I do not have any file to upload. I need at least 1 reference and be certain to answer the questions completely. As a best practice please compare and contrast the difference in employment of a protective service agent and independent contractor.