What does Acts 7:16 mean?

Stephen is finishing his story of how the Israelites came to Egypt. In the beginning, he showed how the Israelites were far from respecting God's prophets. In truth, they have a long habit of persecuting them, starting with the tribal patriarchs who sold their brother Joseph into slavery (Acts 7:9–14). Now, Stephen returns to the historical proof that God is with His people no matter where they live—including Egypt. Soon, he will return to the idea of rejected prophets, focusing on Moses (Acts 7:35–43).

There is some confusion about the geographical locations mentioned here. Abraham bought a field in Machpelah from the Hittites, west of the Dead Sea at Hebron, to bury Sarah (Genesis 23). Abraham and Jacob were later buried in the same place (Genesis 25:9–10; 50:12–13). Jacob bought a piece of land to pitch his tent near Shechem, north of Hebron, about half-way between the Dead Sea and the Sea of Galilee (Genesis 33:16–20). This is where Joshua 24:32 says Joseph was buried.

So, why is Stephen saying Abraham bought the land where Joseph is buried? There are two possible explanations: 1. Stephen has very little time to explain, so he combines the two events and locations. His Jewish audience would know what he meant. 2. Abraham did buy the land initially, in an unrecorded transaction, and Jacob reaffirmed that purchase as Isaac did when he reclaimed the well of Beersheba (Genesis 26:26–33) which Abraham had dug (Genesis 21:22–31). It's even possible that Abraham bought the land when he built his first altar to God there (Genesis 12:6–7).