For just taking one bike I pop off both wheels and set it in the trunk. Easier to take off the rear wheel than bothering to fold the car seats and it keeps the bike totally hidden if I want to stop somewhere. Also have both rear and roof racks that I use mainly when driving Sag since that lets me take up to 4 other people and 5 bikes. I'd vote against a roof rack based on the number of stories I've heard from people who forgot about the bike when entering their garage or a low overhead drive-through.