Grand Buick GMC is a Denver area Dealin Doug Dealership selling Buick and GMC cars, trucks, and SUVs. Knowing that, keep in mind that nobody beats a Dealin Doug Deal, nobody. If you find a bonafide deal, come tell us about it, and we will beat it or give you the car! If you're looking for a truck with a punch, we have lifted trucks here for sale. We are located at 2000 West 104th Avenue in Thornton, Colorado close by to Westminster and Broomfield.