Stripping a skyscrapper to its frame?

[frischee112]

According to wikipedia, the Trump International Hotel and Tower in New York (http://en.wikipedia.org/wiki/Trump_I...w_York_City%29) was stripped to its skeleton in the late 90s and the facade replaced with what it is today.

How easily is this done? Could it potentially be done with any structurally sound skyscraper? Has it been done on others? And what kind of cost is involved?