Abraham buys a Burial Plot

Why would a whole chapter of Genesis be devoted to the process of buying a piece of land for a burial site? It seems that there may be at least a couple of reasons. In the first, place it demonstrates the integrity and humility of Abraham and gives us an example of how we should live our life with integrity and humility. Abraham did not just take the land because of his status in the community, rather he bought it outright according to the customs of the land. Sometimes as missionaries we were granted privileges and exceptions because we were thought to be rich or in a position of authority. Often we were tempted (and sometimes yielded) to take advantage of the opportunities. It would have been much better to behave as the local custom dictated. And in our daily life the same principal should apply. We do not need to take advantage of our position to gain an unfair advantage.
Second, it demonstrated the respect and love Abraham for his wife and teaches us that we should respect and love our spouses as well.