Sarah dies at 127 years old. Abraham negotiates for some land as he wants to bury her in a cave.
15 My lord, listen to me; the land is worth four hundred shekels of silver. What is that between you and me? So bury your dead.” 16And Abraham listened to Ephron; and Abraham weighed out the silver for Ephron which he had named in the hearing of the sons of Heth, four hundred shekels of silver, currency of the merchants.
"What's 4 hundred shekels between you and me?" reads sort of like something you'd expect from desert peoples doing a deal. I don't have much to add to those, but it's possibly important later.