Online Reputation Management is diverse and covers many areas. It can range from deleting a review on Google to improving the first five pages of Google search results. The price depends on the job and can start at $500 and go up into the tens of thousands.
For example, the most I ever charged was $48k to clean up a politician's sexual allegations from the first page of Google search results. However, a big part of that money is used to pay big publications like Forbes, Entrepreneur, etc.