The important question is:
How will my book compete in the market with similar books?
Before you write your book, you should research your competition. Agents, Editors, Publishers, and Bookstores need this for publishing consideration. Whether you self-publish or traditionally published, you need to evaluate the competing books.
Unicorn for Writers will provide a list of at least twenty competing books that are in print. We will also provide a brief description outlining the similarities and differences from your proposed book.