In a place where they are accustomed to repeat, he repeats; [where the custom is] to recite as is, he recites as is; [where the custom is] to recite a blessing after it, he recites a blessing after it —- everything [must be done] in accord with the local custom.  If one purchases a lulav from his friend during Shemittah, he must give him the esrog as a gift, because it is forbidden to purchase it during Shemittah.

Originally the lulav was taken in the Temple seven [days], and in the provinces [it was taken] one day.  After the Temple was destroyed, Rabban Yochanan ben Zakkai instituted that the lulav be taken in the provinces seven [days] in remembrance of the Temple; and that the entire Day of Waving be forbidden.