Don't sell yourself short. No one will value you. Set a fair price for you, your book, your services, whatever it is that you have to offer. Most of us set way too low a price. Put it a little higher than you would normally be inclined to do. The worst that can happen is someone will come along and steal it.
When you self-publish your book you quickly learn that you have a number of free things at your fingertips you can use to market your book. One of these is your book's price. A traditionally published author would find this a lot more difficult because that decision has been taken out of their hands.