YES! I'll be printing the stretch goal books through DTRPG the same as the core book. Each stretch goal book in softcover will be an additional $30 USD. If you're International, add another $20 for each book (you'll get a code and pay for printing and shipping yourself just like the core book, so the costs are equivalent).
If you want the full-color, limited-edition, signed hardcover of a stretch goal book, add an additional $70 to your pledge per book.
For retailers in the MERCHANT TRADER tier, you'll be able to order any combination of 10 stretch goal books as the goals are unlocked. If you end up wanting 10 copies of two different books, it will be $150 for each set of 10 as an add-on.
(The add-on books are less because the cost of shipping is already baked into each backer tier).
I'll be handling the add-ons myself via a combination of the backer surveys and Google Docs surveys.