Traditional handmade shmurah matzah is recommended for seder use.
Shmurah means watched, and it is an apt description of this matzah, who's ingredients are watched from the moment of harvesting and drawing.
Shmurah matzot are round, kneaded and shaped by hand, and are similar to the matzot that were baked by the Children of Israel as they left Egypt. It is thus fitting to use Shmurah Matzah on each of the two Seder nights for the matzot of the Seder plate.
As is the custom every year before Passover, we traditionally sell all of our chametz, the leavened food items, before the holiday begins.
Since there are many legal intricacies involved in this sale, a rabbi acts as our agent both to sell the chametz to the non-Jew on the morning before Passover and also to buy it back the evening after Passover ends.