Complex sentence: In the mid- 1920s he took over the family estate Groß Stein from his father and became a member of the NSDAP in 1932 and "Allgemeine SS" a year later.
Split into simpler sentences: In the mid- 1920s he took over the family estate, Groß Stein, from his father. In 1932, he became a member of the NSDAP and the "Allgemeine SS" a year later.