Quests: The School
Closest Drop Point: Apartment block
The corpse you're looking for is in the northwestern part of the building.

Quests: Machinery
Closest Drop Point: Apartment block

Quests: Revelations
Closest Drop Point: Central area
The documents will be in an orange bag in the western part of the building.

Quests: Revelations
Closest Drop Point: Apartment block
To find the documents here you'll have to immediately head upstairs after entering. The quest description says it's on the first floor, but this seems to refer to the British English meaning. It'll be in the southwestern part of the building in another orange bag.

Quests: Health Emergency (Crimson Corporation)
Closest Drop Point: Central area

Quests: Fire Station Documents (Crimson Corporation)
Closest Drop Point: Construction area
The documents will be in the usual orange bag in the northwestern part of the building.

Quests: Zakov Outpost (Crimson Corporation), Zakov Outpost (Green Army)
Closest Drop Point: Construction area

Quests: Police Station Documents (Green Army)
Closest Drop Point: Construction area
The orange bag with the documents will be in the northwest part of the building.

You can also use the key dropped by Valentin here. The armory is in the northern part of the building.

Quests: Need for Gasoline (Green Army)
Closest Drop Point: Construction area