Here is a full locations guide for every file, Charlie doll, weapon, lock, safe, and locker in the game. This guide is done in chronological order of the game and with minimal spoilers. Enemies have been cleared out of most rooms in the game so be mindful of the rooms you are entering. Some back tracking is required in the Raccoon City Downtown area in order to fully get everything. While some of the locks and weapons are essentially unmissable in the game, others can be easily overlooked if you speed on by them.
Grenade Launcher (14:31)
G18 Handgun (30:37)
.44 AE Lightning Hawk (32:24)
You will also need to pick up frag grenades and flashbangs as Jill and Carlos as well. The best place for Carlos's grenades are is in the hospital while doing the defence in the back room with the fuse box. There are lots of frags and flashes for Jill spread across the game so hers should not be a problem.