I have a phone # for someone and their address, is there any way to find out their apartment #?

Answer 1

Mail them something, and on the outside of the envelope (lower left hand of the front) write "address correction requested." The postal service will send you a postcard with the complete address within usually a few weeks. They may charge a small fee - not more than a dollar.

Answer 2

if you go to the president or whoever is the head of that apartment complex, and give them the phone number, they can tell you which apartment they're in.