One of the places was on the balcony of the Four Seasons Hotel, where Qin Zhi'ai was as she was speaking to Lu Bancheng, specifically on the top floor standing in front of Gu Yusheng's rental room.
After ending her call with Lu Bancheng, Qin Zhi'ai walked to the emergency exit, pushed the door to the balcony open, and walked a few stairs down. She didn't see anyone on the balcony.
Qin Zhi'ai explored a few other places Lu Bancheng had listed, but she didn't find Gu Yusheng at any of them.
At one point, Qin Zhi'ai called Gu Yusheng again while standing in the middle of the road, but he still didn't answer.
Suddenly she thought of Gu Yusheng's parents when she was about to call him again.
Would he be at the cemetery? He must be thinking of his parents while his grandfather is so sick.