If you have two cars and they put one on each, you should switch them so that the FBI looks like they don’t know what they are doing when it comes time to testify they keep getting the cars mixed up. Do this every few weeks and their testimony becomes unreliable.
Wasn’t there an episode of “The Wire” that had a subplot about this very thing - where one of the cops planted a camera somewhere, some local hood found it and stole it and the cop had to track it down.