While looting for piece of loot scattered, you should be able to find LOCKED or UNLOCKED containers with loot that spawn around, such as some sort of big briefcase in the military base. Instead of pressing “E” on it, and looting it, you should be able to pick it up if you dont have enough storage/tools to open it or just want to get out of a high risk area. You could for example place it at the back of your truck.
You could come up to a container and hold or press a button, then your character would place the case (depending on the size) over his shoulder. You could only use 1 arm in that situation or nothing at all. Then you can place it down again where ever and move it when ever. These briefcases could be unlocked or locked in any different way such as with a key or a passcode.
This feature would also apply on crafted storages, so when you get inside of someones base, you could (maybe there should be other tools needed for this), move a couple first to your truck and go for example, instead of shooting it all down and not having any storage.
Let me know what you think.