Applying texture maps

In applying texture maps to models, I have tried two techniques.

1.) Create and apply a map to each surface of a building, individually, for example. That can, in turn, result in several maps associated with one model.

2.) Create one, large map then spread it over the entire model, using the apply maps utility to get the right cover for a particular surface.

Am I making sense? If so, which technique is more efficient, or, does it matter?

An opinion will be greatly appreciated.

Cheers, to all!