Hilchos Pesach – 6 / searching for chametz

1. A person who has several homes to search, or, in addition to his home, he also has a shop, car or storage room to search, recites a single blessing for all the inspections, since they are all part of a single mitzvah. The walking between location is not considered a hefsek-interruption (Shulchan Aruchand Mishnah Berurah 432).

2. An individual who does not want to, or cannot, search his entire home by himself may place several members of his household near him when he recites the blessing. Then, after they hear his blessing, each of them can then go and search separate rooms (ibid.).