Rising Buildings Animation I need some help. I am looking for the easiest way to create the animation of a few rising buildings. The idea is to start the animation with a natural landscape and then to make appear from nowhere 5 simple high rising buildings that grow till hiding the beautiful natural landscape. 

My problems are essentially two:


how to make the first basement appear from the nowhere, as it seems to me that I can't add a keyframe when there is no object, a part from the landscape;
how to make the buildings grow one after the other but, at the same time, separately; I try to explain: I have tried to copy and paste upwards the first floor to create the top floors of the first building and then do the same in other positions of the plane for the other buildings. But when I animate, the floors of the other buildings seem to shift from the first one, as if the animation recorded not just the new rising buildings, but also the movement of the copied floor, from the original building to the others.


I don't know if I have been clear enough. I have looked for a video tutorial for days, but without any result. 
I am really a first-time blender user and I am doing this project for a university examination, so I hope somebody could help me.

Thank you a million for any advice.

Enrico
As to the first question: I think toggling the "restrict rendering" button using keyframes should allow you to make the object appear seemingly from nowhere.  The object is there in all frames, but it is not rendered until the frame where you turn rendering on.

I am assuming you know how to insert keyframes (hover over the control on the frame you want, set to the value you want, and type "I")