I think Dak would command $30 on the open market. That's basically the bottom level when you consider what quarterbacks will be making.
But … no team would give up two first-round picks to take Dak off the Cowboys' hands, and I dare say one first-round draft pick would be stretching it.
Dak is a leader, gutsy, a team player all the intangible qualities you'd want in a quarterback. But just like Tim Tebow, he just isn't a franchise quarterback. More like Alex Smith, Kirk Cousins and, shutter, Andy Dalton.