This goes for any used car but its important for terminators due to the way these cars are so often modded and tuned. Bring an OBD2 reader to your test drive. In addition to the obvious of checking for current codes you can also make sure that the readiness monitors, or emissions monitors, are all complete. This ensures that the owner did not reset the fault codes just prior to you driving it and therefore hiding any check engine lights. I did everything else including a compression test but didn't do this when I bought my low mile terminator. Two hours into my drive home I get a check engine light. Most likely from the canned predator tune in the car. I took the car to get a dyno tune right away and set things straight. This is also something you should plan on doing for piece of mind.