His publicist hit my site - there are four "books", together they are sold as one paperback that is under 300 pages in length. A "book 1" version won't be sold on paper, and the full 300 pages is about $12 in price.
That makes this a novella length work, probably around 75 pages, assuming it can even stand alone, or just part I of an actual book (which puts it back into the teaser sample trash pile, for me; some of the publishers have decided this is all they need to give away, since the fake freebies work so well at Amazon -- it may not build sales on it's own, but it inflates rankings and that alone can build sales).
If this were a graphic novel, then shorter editions would make more sense. Presumably that is not the case, for this book.