"I've done plenty of breaking and entering!" Dick cried, looking at her with a smirk. "Just not breaking and entering into buildings." He said, his eyes swooping over Lacy before jumped up and grabbing a hold of the fire escape. He pulled himself up a level and began to quickly scale the shaking, metal steps. 

Almost all of the windows of the building were broken, Dick just had to choose one to sneak in through. It was the middle of the day, so the sooner he picked one the better. If Dick was remembering correctly, this was the building that Senna's parents broke into the night they were arrested, the night that Senna's biological father was killed by police. 

And knowing how Senna thought, this would be where she'd camp out.