Pros and Cons of Trad Publishing vs Self Publishing This gave me an interesting thought.....You only need an ISBN Code ($125 scaling down by volume) for each different type of publication (Ebook, AudioBook, Paperback, Hardbound Etc..) If you want to get into Bookstores & Libraries. But everything I'm seeing of late more authors are selling direct through their sites and at live events than through Kindle, Kobo, B&N etc... Why not instead put a QR code on the back for your own website or catalog? Or both if you have an ISBN. Remember a free ASIN from Amazon is not usable anywhere else, and if yo get an ISBN assigned by another aggregator like Direct to Digital they OWN that code and can limit your usage of it. Desperately in need of updating several websites and had this thought.