Broken brake system

Date: 9/28/2018

I was at a garage or body shop and I was looking at a dark blue car someone had left. It was an early 2000's model convertible. I looked around and seen nobody was there so I got in to drive around the parking lot. As I was backing up I noticed it took a little longer to stop/slow down than it should have been. I was confused cause the only thing that was supposedly just the body not anything internal. I brush it off and go to park it and as I try to stop it it just keeps driving. At this point the brake is to the floor and the cars ready to hit a house. It finally stops and I get it into a parking spot.