To publish through barns and n, costs about $2000.00
Amazon or who they pub through get 30-40%
Authors through most publishing houses get just 10% of the costs of the book.
Good example, my book, poetry costs 14.95 on most sites, I get $3.10 per book sold
The author of any book only gets 10% of the cost of the book the rest of it goes to the publisher editors etc. etc.