Which Tax Office branch serves individuals living in Beylikdüzü?

You need to use «Avcılar vergı daıresı müdürlüğü» («Avcılar Tax Office»).
goo.gl/maps/sTHjoySi87SUpUj57

Cihangir, Ormanlı Cd. Avcılar Hükümet Konağı No:55, 34310 Avcılar/İstanbul

Beylikdüzü individuals are served on the 3th floor.