Complex sentence: On 17 February 1981 Kujau flew to Stuttgart and gave Heidemann the three recently prepared diaries, for which Heidemann only gave him 35,000 marks, not the promised 120,000--40,000 marks per diary--from which Heidemann would also claim a 10% commission.
Split into simpler sentences: On 17 February 1981 Kujau flew to Stuttgart and gave Heidemann the three recently prepared diaries, for which Heidemann gave him 35,000 marks. This was a great deal less than the 120,000 marks--40,000 marks per diary--promised to Kujau, from which Heidemann would also claim a 10% commission.