I have been doing a lot of research and in the end pricing of my books comes down to two options
1st. an industry standard keep the prices the same, and rely on the quality of the product
2nd. make the books so you can make some money but let the quality of the product sell the quantity
In short, I have devised a new plan to make money and keep the cost of the book down.
Therefore, the new prices for the books shall all be different, instead of the same for e-book, paperback, and hardback.
The new prices shall reflect the minimum I can sell them and still make a living