Repo people can take your car without the keys by towing it. All they need to do is lift your vehicle onto a truck and drive away.
In fact, the repo process has gotten fairly aggressive in recent years. With new towing equipment, repo people can easily tow your car no matter where it is. It’s been known to happen while owners are in gas stations, eating in restaurants, or even just shopping at the grocery store.
Each state has different regulations on what repo agents can or can’t do, but some states are pretty lax with their restrictions. Repo agents can hotwire your car, take it from your property, or even remove it from a locked garage in some instances. Of course, these are extreme situations that only occur if you hide your vehicle from the proper owner.