I'm going to say that there is a reverse correlation to "Free chapters".
Being able to read 1, 2, 3 (or even 10) chapters doesn't add anything to the price.
If I looked at the book today with NO free pages I'll probably not buy it for $8.
If I look at the same book, with free pages, in a few months time I may read a few pages decide that I like it, and buy it for $8.
So the free pages increase the likelihood my buying it irregardless of the price.
She could be from the UK, Canada, etc. They all speak an odd version of English.

And they pay a higher price.
Knowing nothing about her book I would say that, until she builds a reputation, she should have a lower price.