http://upload.wikimedia.org/wikipedia/en/6/69/Diffrentstrokes.jpg

http://ephemeralnewyork.files.wordpress.com/2009/08/diffrentstrokesbuilding.jpg?w=300&h=225

Arnold and Willis Jackson moved into the penthouse in the building below, 900 Park Avenue, to live with soon-to-be adoptive father Mr. Drummond. The circular driveway the limo lets them off at in the opening credits is a lot smaller in real life.

more:

http://www.thecityreview.com/ues/parkave/park900.htm

the cat statue:

http://www.panoramio.com/photo/3273111