This chapter sounds like a drawn-out real estate transaction, but it shows two things: Abraham was so important that Hittites, people of a major international power at the time, had great respect for him. Abraham’s first title to land in Canaan was to bury Sarah, who was very significant as the mother of the promised son by way of God, Yitskhak.
The events around Sarah’s death are not mentioned simply as a marker of time. She was a prominent person in her own right. Her Biblical biography is the only one of a woman that mentions her age at the time of her death as well as the elaborate negotiations surrounding the location of her final repose. The negotiations for her burial place have implications into the present day.