Detectives say the burglars have been stealing the homes' copper pipes, copper wiring, appliances, fixtures, pool filters and air-conditioning or heating systems.
Police suspect the burglars are pulling trucks into the garage to load the items in secret. It's also possible the thieves disguise themselves as movers or repairmen.
The Simi Valley Police Department is asking the community to keep an eye out for suspicious vehicles, broken windows or doors and signs of structural damage. Residents are also asked to remove papers and fliers that accumulate in driveways and on porches.
Anyone interested in creating a Neighborhood Watch Program can contact Simi Valley Crime Prevention Specialist Jean-Marie Maroshek at (805) 583-6276.