As for the environment (including the nearby existing buildings and so on) of one designed building in an architecture animation, when is it necessary to be modeled, when not?

When modeling the real environment, how to realize it? By modeling software like Maya, 3Ds Max, etc.? Or using an image-based modeling software like Canoma, Photomodeler? Or any other methods?

And should an architecture animation has a high resolution? How high at least then (pixel)? Does anyone have any good example of architecture animation including the real environment?