Without a view camera the perspective is a function of the point of view. Buildings (or anything) will look straighter (less tapered) if you move the camera further away. Then you will need to increase the focal length to compensate for the more distant camera.

In both images above the camera is 0.365 PU above the ground. In the the top image DollyZ is -0.210000 PU, and the focal length is 25mm. In the bottom image DollyZ is 6.366 PU, and the focal length 200mm.