You don’t have to render the whole building for stunning architectural renderings. You can isolate details such as windows or columns to produce renderings with a ton of impact. Glass, metal and concrete structures, are full of graphic details that are perfect for producing this type of renderings, but you can also find them in older buildings.
The key to this style of rendering is simplicity, so look for areas of the building that you can isolate from their surroundings, or repetitive patterns in the structure. Then try rendering them either straight on to make the most of repetitive patterns, or at a deliberate angle for more dynamic images.