Any property owned by a Jew that might contain a kezayit of ĥametz must be searched. Therefore, the kitchen and the dining room where people eat must be searched, and any room, storage space, or porch where people sometimes bring ĥametz must also be searched (SA 433:3-4).
Clothing closets that are not generally used during the course of a meal need not be searched. However, if there are children in the house, closets must be searched, because the children may have opened them while handling ĥametz, or may have even hidden ĥametz in them. Closets that are too high for children to reach need not be searched.
One must also search cars and carrying bags in which he sometimes puts food. Adults who generally do not put food in their pockets need not search them. However, the pockets of children must be searched. Garments that were washed and had their pockets emptied out beforehand need not be searched on the night of the fourteenth (see section 8 of the present chapter). One who does not have a home does not recite the berakha when searching his car or pockets, for the Sages instituted saying a berakha only when searching a house (Kaf Ha-ĥayim 433:91).
The stairwell of an apartment building or condominium is shared by all of the building’s occupants, and therefore they have a collective obligation to search it. In such a case, one of the occupants should be given the responsibility of performing bedikat ĥametz. Open yards need not be searched because we can reasonably assume that animals ate any ĥametz that might have been there. However, if there are alcoves in the yard that might contain ĥametz, they must be searched, because animals may not have crawled into them to eat the ĥametz. Likewise, if one knows for certain that there was ĥametz in his yard on the night of the fourteenth, he must search it, because he cannot be certain that animals will eat it by noon of the fourteenth (MB 433:27, citing Mekor Ĥayim). An enclosed porch, even if it opens into a yard, must be searched.
Ownerless public domains need not be searched, for even if they contain ĥametz, no violation has been committed. This is because such ĥametz is not in the possession of any particular Jew, and the ĥametz prohibition only applies where ĥametz is in the possession of a Jew, and not in an ownerless domain (SA 445:3; MB ad loc. 18. Garbage bins are discussed below, 5:5).