Each dealer has his own pricing - some won't give more than 15& while others may go to 25% or more. You just have to bargain hard and be willing to go to a different dealer if you don't get the price you want. I suggest contacting several once you know the floor plan and options you want.
Tiffins in general are in demand, and the new Breeze even more so. I know of dealers who cannot get them fast enough to meet demand, so they have little incentive to discount deeply.
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL