Introduction
In this tutorial I hope to provide an overview of how I created the scene and discuss a few of the key techniques I used. The main job was the texturing and so this will form the bulk of the text, however I have also touched upon some of the modeling and lighting.
The first stage before building any 3D scene is to do some research into the subject and find some reference photos. My goal in this case was to choose a topic that could take advantage of a variety of different materials and textures. I had recently seen an interesting program about Dharavi, a slum in Mumbai, and this came to mind while I was trying to think of a suitable topic. The materials used to build the many houses were varied and utilized a chaotic mixture of wood, metal and plastic.
This instantly seemed like a perfect subject and so I started to create a scene that represented the outer walls of a slum somewhere in the tropics. I liked the idea of a large wall that descended into a tipping ground for rubbish and effluence with some cramped buildings perched precariously along the edge.
Modeling & Lighting
My usual approach is to build some preliminary geometry and create the main volumes in the scene before adding a camera and experimenting with the composition and lighting. I began by creating the key components first, which in this case was the main wall and row of buildings. Each of these started life as a box which was then converted into an Editable poly and modified using simple extrusions and chamfers etc. My aim was to retain as much detail as possible for the texturing section and Fig.01 shows the main sections of geometry that make up the scene, which are little more than boxes.

Fig. 01
The photos I found of slums all seemed to incorporate metal panels that had been used to either create walls or perhaps seal the sides. These were necessary to add interest to the scene and help create an authentic appearance, along with some corrugated roofing.
Fig.02 shows a render that includes these panels and some additional structures such as the bridge and pile of rubbish beneath it. I only wanted to model the most noticeable volumes, which would be apparent from the camera angle, as the texturing was going to be used to describe much of the detail.

Fig. 02
As this was going to be a still I opted not to model the components that make up the rubbish, but instead chose to use a texture which we shall see later in the tutorial.
The metal panels along the front of the buildings were all modified from one piece and then scaled and re-positioned. I altered the outside verts to ensure each had a unique shape and then applied a Noise Modifier to create some random dents and an uneven surface. I used a similar technique for the wooden poles and bridge supports.
The two lamps hanging from the wire were derived from a lathed spline and the wire itself is simply a renderable spline.
The lighting in this render is representative of the final still and is generated form a single mr Area Spot with some bounce light created from a dome that encompasses the scene (Fig.03).
You can see, the dome here has the Self Illumination set at 100 and is used in conjunction with Final Gather.

Fig. 03
The Area Spot has been tinted slightly yellow to represent the sunlight and in order to create some softer shadows I have increased the Radius under the Area Light parameters.