Selling on-line digital books is a vibrant market but, especially for fiction, very competitive. HTML features are tricky & color pages are hard to get to flow right as every vendor has their own complicated specs. For each platform you choose to promote, a well-crafted E-book is necessary, or it just will not sell.
Some authors prepare this themselves from the graphics files we provide after printing your book. Most choose to have Wise Publications do it for about $80 per site so they can focus their energy on the extensive social media campaigns. Usually we add one platform at a time as your book finds a fan base.