Complex sentence: In Australia, most Seras will have required three-point seatbelts and side impact beams to be fitted for compliance, as such it may be beneficial to import a later model Phase III to avoid this third-party work.
Split into simpler sentences: In Australia, most Seras will have required three-point seatbelts and side impact beams to be fitted for compliance. There may be benefits to importing a later model to avoid this third-party work.