You will start outside in the hallway and be told that the key is under the rug. When you look under the rug the key is gone. There will be a crack in the floor board, use your press card with the gum stuck to it in order to pull the key out from inside of the crack, you can now use this key to unlock the door and go inside. Once inside the old man will sit down and you will automatically move on to the gallery.
You will get to the street where the gallery is and fine Laine sitting outside the cafe (I guess he finally settled the bill). Speak with him an get through all conversation options. When he asks, agree to go to the gallery. After a walk you will both end up inside the office in the gallery.
Sit down on the couch next to Laine and begin talking, keep doing this until ye both have a glass of champagne. When the champagne is sitting next to you on the couch, pick it up and it will now be in your inventory. Use the glass on Laine and it will spill all over him. When he jumps up off the couch, pick up the folder under the couch cushion and read the notes. After you have read the notes you will end up back at the apartment again.
While back at the apartment you can engage in further conversation with the old man sitting at the table.Once the conversation has ended, speak with Nico and she will send you on a phone number for Waterloo Motors. Bring up your phone and give the number a call. After speaking with the guy on the phone your work will be done. Somehow you are now going to walk out of the apartment and end up in London.