I had just picked up a rental car from taking in my car that got rear-ended and went to get coffee at a Starbucks. I pull out of my space and a car 2 spaces over pulls out too. I'm already out of my space and I'm going the same way out as the other car but I'm waiting for him to pull out too because he's in front of me. He starts to slowly get closer to my car and so I give him a courtesy honk to let him know I'm behind him. Then he's about to hit me and I lay on my horn so he can stop. He proceeded to back into me, hits my rental car that I just got not more than 15 minutes ago and drives off in the parking lot like nothing happened. I run after the car before he leaves the parking lot and stop him and get him to pull over. This man was 84 years old and had no idea he hit me and was confused on why I was hysterical on stopping him from running away from the scene.