How Cowboys trading Dak Prescott would have multiple uncertain layers

The Dallas Cowboys probably won't be looking to trade Dak Prescott anytime soon.But there's no time like mid-July to consider the possibility, which is what ESPN's Bill Barnwell does in a new article on Thursday.Barnwell's premise is to find what each of the league's top players would cost in a trade if they were available.It's a good way to assess value across the league, and within individual teams.For Prescott, Barnwell lists his trade cost as "one first-round pick and more," but his analysis is even more interesting.MORE: Brandon Aiyuk's latest decision probably ended his NFL careerHow would a Dak Prescott trade work?A Prescott trade would have value questions all around, because not only would there be the matter of a return cost, but also his present contract cost.Prescott makes $60