For the SFWA grant series books, the grant funding was enough to license some of the art pieces. For our in-house books, the usual profit margin × average sales volume per book makes it impossible to pay artists or designers at market rates. We'd net a loss to the tune of several hundred $$$ or more per book. So, early on, we decided to just muddle through with our own designs. They're a bit rough around the edges sometimes ... but they're free! 🤣