They've taken his computer, a couple of VCRs, tools, watches and other property, worth about $20,000 (pounds 12,000). A brawny Rottweiler didn't scare away the burglars - the dog was stolen too.
Somebody even made off with the business card of a police officer who investigated one of the first burglaries. Hence the sign. "Maybe it'll do some good, if [burglars] can read," said Mr Farrell, 51. "It was the only thing I could think of doing - just let them know there's really nothing left to steal."
Police have no suspects, but Farrell said he thinks gang members in the neighbourhood may be responsible. He has started sleeping with a gun, takes his remaining VCR with him when he goes out and rents a storage unit to stash other items.
"I'm afraid to leave my house, because I never know what I'm going to come home to. You don't know what these guys are going to do." He has also installed bars on his windows and is putting in steel doors, new locks and motion-activated lights. "All you can do is move or live in a prison," he said.