This mod replaces gage packages with additional loot, spawns more loot on heists at certain non-Gage positions (see screenshots) and also gives dozers a chance to drop loot on death.

Every heist has its own configuration file (in the heists folder). They can be opened with a text editor.
The dozer feature can be configured in dozer.json.

Limitations:

• The mod will only work on heists which cannot be finished only using additional loot (the heists where the main objective is not to secure X number of bags). The only exception here is Shadow raid, because almost all additional loot there is not easy to get.

• Works on Mayhem difficulty and above.

• You must have at least $300,000,000 on your offshore account.

• There are also limitations for the maximum amount of bags you can get rewarded for on every heist. That is supposed to balance the mod and make it less cheaty. More info:
  https://steamcommunity.com/app/218620/discussions/14/358415738207022675/ (thanks to Manager of the Melons for finding this thread)

It will work only if you are the host. It will work for clients, they don't need to have the mod.

Installation:
Standard BLT installation.

If you don't know what BLT is:
Google "payday 2 BLT" and install it.
Put the "Gage loot courier" folder to your PAYDAY2\mods folder (the BLT will be looking for PAYDAY2\mods\Gage loot courier\mod.txt file, so make sure you do it right and it is there).

List of heists and loot (the heists that support non-Gage loot are marked with "+"):

+Firestarter day 2 - cocaine (white packs), assault rifles (interactable cases)
+Firestarter day 3 - money (as in deposit boxes), gold (as in deposit boxes)
Transports (except train heist) - jewelry, money (as in deposit boxes), gold (as in deposit boxes)
Mallcrasher - jewelry
+Nightclub - cocaine (white packs)
+Ukranian job - jewelry
+Rats day 2 - money (as in deposit boxes)
Rats day 3 - money (as in mendozas' cases)
+Shadow raid - cocaine (white packs), gold (as in shipping crates), money (as in shipping crates), assault rifles (interactable cases), artifact (as in shipping crates)
+Big oil day 1 - assault rifles (interactable cases)
+Election day day 2 plan A - money (bucket of money), gold (as in bank vaults)
+Hotline miami day 1 - money (bucket of money), assault rifles (interactable cases)
Hotline miami day 2 - cocaine (white packs), money (bucket of money)
+Murky station - pistols (interactable cases), rifles (interactable cases)
+Counterfeit - counterfeit money (stacks)
+Alesso heist - money (plastic wrapped)
+Slaughterhouse - gold (as in bank vaults)
+Hoxton revenge - evidence (boxes)
+Golden grin casino - money (as in bank vaults)
+The bomb: dockyard - cocaine (white packs), gold (as in bank vaults)
Beneath the mountain - lost artifact, prototype
+The diamond - artifact (ancient pot)
+Meltdown - cocaine (white packs), assault rifles (interactable cases), gold (as in bank vaults)
+Santa's workshop - present
+Biker heist day 1 - cocaine (black packs), assault rifles (interactable cases)
+Election day day 2 plan C - money (as in bank vaults)
+White xmas - pure cocaine
First world bank - gold (as in bank vaults)
Boiling point - test subject
+Panic room - cocaine (white packs)
Stealing Xmas - money (bucket of money)
+Brooklyn 10-10 - assault rifles (interactable cases)
+Green bridge - jewelry, money (as in deposit boxes), gold (as in deposit boxes)
+Scarface mansion - money (as in bank vaults)

Out of frame - gold  (as in bank vaults)
+Golden Cruise - gold  (as in bank vaults), cocaine (white packs), counterfeit money (stacks)

Questions you might ask

"Is it possible to spawn loot which does not belong to the current heist?"
Possible, but it will require all clients to have the mod.

"Is it possible to add additional shipping crates?"
Yes, but they will not have anything in them.

"Additional meth ingridients, maybe?"
When you pick them up, the game does not give them to you.

"Some loot cannot be taken because of its position, rotation?"
Yes. I'm not going to fix it.

"Will the game mark me or my clients as a cheater for securing too many bags?"
It should not. I tested it with friends, but it did not mark me or them. Looks like it only marks you if you get a bag out of nowhere, but here the loot really exists from the start. It may theoretically mark a badly desynced client who secures a bag and if due to desync it looks like he secures two bags. But that's an incredibly rare situation and I don't know for sure.