I put mine inside the car. Rear seats fold down, bike goes in rear wheel first, drive side up. It's easier for me to handle that way.

If we're going to be gone from the car for a while, I cover the bike with a blanket or leave it locked to a rack and load it later. We had a car broken into a few years ago, so now I'm paranoid.

I've been rear-ended every year I've lived in my current city, and I don't think I could bring myself to use a rear-mount bike rack. A hit from an uninsured driver could get expensive in a hurry.