New York rooftops - Props

As my work as a concept artist has come to an end I have been set with a task to texture various objects. Although at the beginning I wasn't very keen on doing this task I have quickly realized that I enjoy it.
For this task I am using Maya where I lay down UVs to the graybox and then I export it with desired resolution. I tend to use a higher numbers when it comes to bigger object such as buildings, and smaller for the assets.
Our idea for the game level included a flooding and post-apocalyptic scenario so I am trying to reflect that in the texturing work. In many cases I am adding worn out textures, scratches and graffiti.
When I am finished with texturing I usually save my UV image as JPEG and I create a bump map. It gives a nice depth to the object and really pushes out the details. It is very important not to go over the top with the intensity of the bump map as it looks unnatural.