Photoshop Building to get an idea of how it will look with improvements

Looking for photoshop help to change the color of a building and add a new section in the photo to the top of a building to see what it will look like when the project is done. I would like someone that has done work like this in the past and could show examples of past work. Would need a couple of options for each of the two buildings. We want to see how they would look painted a light gray with dark gray accents and adding a sign to currently non existant addition at the top of the building. I have added in roughly where the add on should be. A couple of examples of building materials and Our current channel letter sign. White Building - With a Dark Gray paint on the bricks and Light Gray Trim Add on an extension up top Red Building - Paint Light Gray on the bricks Dark Gray on the trim and accents. Add an extension on the roof and add the At Home Sign to the extension. Buildings need to compliment each other without being the exact same.