(1) If the alienor and the acquirer agree that the alienation is to include the accessories of the plot of land, the acquirer also obtains, together with the ownership of the plot of land, ownership of the accessories in existence at the time of the acquisition, to the extent that they belong to the alienor. In case of doubt it is to be assumed that the alienation is intended to extend to the accessories.
(2) If the acquirer, on the basis of the alienation, acquires possession of accessories that do not belong to the alienor or that are encumbered by the rights of third parties, the provisions of sections 932 to 936 apply; the time at which the acquirer obtained possession determines the good faith of the acquirer.