I’ve been ghostwriting books for several years. See
my portfolio. What I have experienced is that each
book is unique. Each person who wants their book
ghostwritten is unique. Each person has their own
kinds of information for the book. The amount of
information provided can cut down on research the
ghostwriter might have to do. In turn, then, this
decreases the amount of time the ghostwriter has
to spend on writing the book.
The subject matter of the book has to also be taken
into consideration. Will there be illustrations, photos,
etc.? Ghostwriting a book eliminates writing credit for
the ghostwriter. Because of this, the charge has to be
higher than if the ghostwriter was getting the credit for
writing the book.
There a host of things to consider before giving
a quote on how much it will cost to ghostwrite a book.