The goal of a 3d rendering is to give your viewer an idea of what you are thinking, set in a realistic atmosphere. When viewing an image like this, there should be recognizable real world items that give a feeling of actual scale and what a person might perceive if the model actually existed.
3d renderings require modeling, the applying of textures to the model, lighting of the scene and setting up camera views. These projects can be done in varying levels of detail and cost will rise as the level of detail rises.
3D Services 
