All objects has actual size and correct named material applied. In the centre of coordinates in itch file located an empty parent object. To link model into your scene press Shift+F1 -> choose file (coffeemaker_1.blend, coffeemaker_2.blend, coffeemaker_3.blend) -> choose group (coffeemaker_1, coffeemaker_2, coffeemaker_3) -> select an empty parent object (coffeemaker_1_parent...)  and locate or rotate in your scene. Textures in .png format are included