What maintenance step should an investigator take before using a vehicle for surveillance?

Ensuring the gas tank is full is crucial for an investigator preparing to use a vehicle for surveillance. A full tank guarantees that the investigator can operate the vehicle without the interruption of needing to refuel, which is particularly important during surveillance operations that require discretion and lengthy periods of observation. This step helps avoid unwanted attention or distractions that could arise from stopping for fuel, ensuring that the investigator can maintain focus on the surveillance task without unnecessary interruptions.

While other maintenance steps like checking tire condition, cleaning the interior, and verifying insurance are also important aspects of vehicle readiness, they do not directly address the immediate operational needs during surveillance. The risk of running out of fuel in the middle of a critical moment makes ensuring a full gas tank the most pertinent maintenance step to take prior to setting out on a surveillance mission.