I narrowed it down to something around my next door neighbor's house. The issue was there was something broadcasting a signal that covered the same range that

I narrowed it down to something around my next door neighbor's house. The issue was there was something broadcasting a signal that covered the same range that my car key fob did, so I couldn't lock/unlock my car unless I was right up on it. But the signal was intermittent, and I talked to all the neighbors in all three units, and none had anything that sounded like it could be the culprit. It eventually just stopped happening, so I never tracked it down.