‘Now Ephron was sitting among the children of Heth. And Ephron the Hittite answered Abraham in the hearing of the children of Heth, even of all that went in at the gate of his city, saying, “No, my lord, hear me. I give you the field, and I give you the cave that is in it. In the presence of the sons of my people I give it to you. Bury your dead ”.'
The conversation is taking place before the leading officials of the city. This is a public sale requiring the say so of the elders of the city, and especially so because it will alter Abraham's status.
Ephron continues negotiation. He is willing, but if Abraham wants the cave he must also buy the field it is in. This would probably put him under certain feudal obligations. The ‘giving' was not expected to be taken literally. They are in fact engaging in hard bargaining.