Complex sentence: In some areas, garage sales have taken on a special meaning to a community and have become events of special local significance: large areas of a community then hold a communal garage sale involving dozens or hundreds of families at the same time.
Split into simpler sentences: In some areas garage sales have taken on a special meaning to a community and have become events of special local significance. In these situations large areas of a community hold a communal garage sale involving dozens or hundreds of families at the same time.