The night before the Seder (Sunday March 24th, 2013) after 8.00 pm, once our house is clean of hametz and ready for Pesah, we do the bediqat hametz, which is the last inspection to search for any hametz food that might have remained involuntarily in our property after cleaning.
That night, with the aid of a candle or a flashlight, we search all spots in our house where we might have brought and/or stored food. We should especially search the kitchen, food storage rooms, the pantry, the refrigerator, the freezer and all other places in which we might have eaten or kept food. In the bediqa we are looking especially for hametz "food" that we could have overlooked during the cleaning process, and not so much for hametz crumbs, which will be rendered hefqer--ownerless--by the bitul, when we declare our hametz ownerless.
Attention should be given also to cars, since it is not uncommon to eat or keep snacks in a car. Cars should be washed and cleaned before the night of the bediqa and then we should search them usually after we search our homes. We should also search our office or place of work, because we often bring food there. If it is impossible to search these locations right after we do the bediqa at home Sunday night, we should do the bediqa before Sunday night or early Monday morning March 25th.
When a family spends Pesah out of town, the cleaning and the last hametz inspection (bediqa) of the main house should be done the night before leaving home, without saying any berakha. The hametz found should be disposed, giving to a gentile or sold. The night of the bediqa, Sunday March 24th, the family should search for hametz in the house or in the Hotel room where the family will stay for Pesach, but this time with the berakha.
Watch HERE why is important to learn Hilkhot Pesah