What does the Pasuk mean when it writes "Vayakam Sedei Efron... "?
Rashi #1: The field of Efron now entered the domain of Avraham.
Rashi #1: The field rose in esteem, from the domain of a Hedyot to that of a king. 1
Malbim: Together with the next verse "l'Avraham l'Miknah", it means that Efron gave a document, and it became a total Kinyan through Kesef and a document. 2
Why does it repeat below (Pasuk 20) "Vayakam ha'Sadeh"?
Rashbam (Pasuk 18): Although Avraham acquired the property with a Kinyan Kesef, he did not acquire the rights to use it as a burial plot until he had buried Sarah there.
Riva: From Efron he bought the property, and from the mayor he bought the rights to make it a burial plot.
Ohr ha'Chayim (19): The field left Efron's domain when he received the money, but Avraham acquired it only through burying Sarah.
Malbim (20): Afterwards, all Bnei Ches agreed to change their enactment in honor of Avraham, who became a resident, and let him designate the cave for a cemetery.
Why does the Torah add "v'Chol ha'Etz
Bava Basra, 69b: This teaches us that when one acquires a field, the borders (including the trees that are planted on it 1 ) are included in the sale.
Malbim: The Torah mentions borders written in the document.
See Torah Temimah, note 13 who, citing Rishonim, clarifies this Halachah. Ha'Emek Davar