Most serial killers attack their victims by pulling them into their vans while the victim is attempting to get into their car. Approach your car from the rear so you can get a clear look in the back seat of your car and have your keys ready. Don't spend time at your car door fumbling to find keys. Once inside your car, immediately lock your door and be ready to exit the garage promptly. Do not use stairs.
Stairwells are excellent hiding places for predators.
Use an elevator instead. Be wary of entering an elevator if there is only one person inside. If you are the only person on the elevator and someone suspicious looking is getting on, then get off. Taking a few more minutes to safely reach your floor is time well spent. Do not stand back in the corners of the elevator, be near the front, by the doors, ready to get off or on.