It completely depends on the prestige of the agency, the geographic and economic factors. In the United States, getting a book from a reputable ghostwriting services agency will burn a sizable hole in your pocket. They can charge upwards of 20K. Some even charge 50K for a 300-page book. My suggestion is to look for more affordable options i.e., agencies that are relatively and doesn't charge a huge premium.
If you are interested in publishing books and want ghostwriting services so must visit the link below for pricing and details: https://bookpublishingandmarketing.com/
ebook ghostwriting service charges vary widely based on project scope, complexity, and expertise. Prices can range from a few thousand dollars for shorter projects to tens of thousands for books. It's essential to discuss specifics with service providers for accurate pricing tailored to your needs.