These renderings are my first attempts at "realistic" renderings. The few projects I've rendered before were very basic conceptual renderings, without much in the way of materials or lighting. In these I used photographs as a basis for my render views, and then merged the photo and rendering together to give it a more convincing feel.
Please let me know what you think, I'm planning on doing more renderings in this fashion so any feedback would be very helpful.
I think that more detailed lighting effects impinging on the building surfaces would make the structure more convincing. It looks a bit too much like a "model" in your rendering. When you study a real-life view you will see that the building skin will, if it's metal, have certain areas that are a little more reflective or brilliant than others; if stucco or dryvit it will have a little discoloration and possible fine texture that plays into how the impinging light is reflected. The merge of photo & model is quite good.
(I have a number of staff people who specialize in realistic renderings for presentation to our clients and your first stab at this is remarkably good! They also utilize additional outside or 3rd party programs as well as additional Autodesk programs to incorporate special textures that alter the way the light is reflected.)