Complex sentence: Mathias and Chloé fall in love with each other after emotionally bonding about their childhood, and since Chloé wants to stay in the apartment, Mathias decides at the last minute to decline a multimillion offer for the apartment/contract.
Split into simpler sentences: Mathias and Chloé fall in love with each other after emotionally bonding about their childhood. Since Chloé wants to stay in the apartment, Mathias decides at the last minute to decline a multimillion offer for the apartment/contract.