Under $500 a month
Almost always automatedAt this price nobody is manually reviewing your site every month. The economics do not permit it. What you generally get is a tool subscription with a report attached, some directory submissions, and a small volume of generated content. It is not a scam in most cases, it is simply arithmetic: a few hundred dollars buys a couple of hours of anyone's attention, and SEO is not a couple-of-hours-a-month discipline.