Walkthrough

Construction Site

"Lots of empty bottles and cans. It looks like somebody was living here."

Entrance and Stairwell

Follow the hall where you may find a couple Health Drinks on the boxes by the elevator, and pass through the white end door to the stairwell. 2F has a broken lock while 3F and 4F also won't open, with safety warnings on their doors explaining that the roof and floor have crumbled. Continue up and enter the fifth floor.

Fifth Floor

Pass through the other door in the hall to a larger room. Move ahead and around the right corner to notice a section of the wall that looks different from the rest, almost like the re-plastered walls from the first Metal Gear Solid... Equip the Pipe or Maul and smack it till the wall breaks, revealing a 20 Silencer and a pair of legs trapped in the wall... Perhaps some of Snake's handiwork? He must've dropped his SOCOM's silencer...

Note on Silencer: Equip the Silencer while the Handgun is also equipped to attach it, allowing you to fire more discreetly without attracting other enemies, but at a small cost of power. Equip or unequip it as you wish. The Silencer can also be used with the Submachine Gun found later in the game.

Deeper in the room behind you is a Health Drink on the box to the right of the hole in the floor, plus Handgun Bullets on the left side by the mattress. Examine the mattress and drop it down the hole, then hop down yourself.

Third Floor

Two floors below via the crumbled ceilings, find the broken wall ahead and pass through to the scaffolding outside. Move quickly to avoid the Pendulums and follow the path around the corner to Heather's left. When the camera angle changes, jump through the window to the building next door.