The above takeaway has the caveat of getting the most out of your good publicist.
As with any profession, there are variances in the quality of publicists. Not all publicists have the same capabilities or track records. Additionally, publicists will have different areas of expertise. For example, some excel with digital print coverage, while others focus on booking TV interviews.
When choosing someone to represent you, be sure that their niche aligns with the campaign you envision. Ask about their past campaigns, successes they accrued by way of media spots for clients, and the time frame of this work.
There has been a wave of market disruptions and workflow adjustments across virtually every sector in recent years thanks largely to emerging technologies, and public relations is no exception. The pandemic and its fall out, for example, have altered the way publicists connect with the media. Gone are the days of reaching contacts by phone.
What's more, publicists today must have some working knowledge of digital marketing efforts as they coincide with and complement traditional PR duties. New avenues of publicity are becoming available. Which will stick? Which should a client pursue to garner attention for their book or product?
Podcasts are a great example. Several years ago an author may have not put much value on podcast appearances. Now some of my clients only want to appear on podcasts. (I steer them away from this limited method.)
The point is that a great publicist will have a history of wins over many years, as well as recent examples showing that they understand industry trends and have up-to-date contacts. They will also be able to speak intelligently on how a PR campaign fits into larger marketing efforts. Such a publicist will cost more money than one who does not have these qualities.
When weighing your PR options, keep in mind the distinction between agencies and solopreneurs. Agency fees are considerably higher due to overhead costs. Freelancers cost less, but that does not mean that they are any less capable or professional.
The big takeaway: you get what you pay for in a publicist; going the cheaper route may mean you are wasting your time and money in not generating the coverage that you deserve. A good publicist of any cost can validate their worth.