How does it work?
In simple words, the barter menu has been modified so every time you ask a merchant What have you got for sale?, it adds gold to the merchant.

To resplenish gold once a merchant doesn't have enough left, simply exit the barter menu and ask again What have you got for sale?

The delay before the barter menu is also gone, just like Vendor Sale Delay - Gone.

The longer explanation
Merchants keep their barter gold in the same hidden chest they use to keep their inventory, which means it's governed by leveled list laws.

Since the barter gold is technically not on the merchant, you can't pickpocket that gold or temper with it directly, at least not in a live fashion.

To circumvent this problem, this mod adds gold directly on the merchant before the barter menu appears. It's like reverse-pickpocketing, an invisible hand place gold in the merchant's pockets instead.

The final effect is the gold added on the merchant adds up with the barter gold, giving the merchant more gold.

To avoid exploits, the mod removes the gold on the merchant as soon as you quit the barter menu. Killing the merchant or asking What have you got for sale? multiple times in a row will not result in any gain.

How the gold is calculated
The mod offers different versions to replenish different amount of gold. This table illustrate the basis for all the calculations.



When deciding how much gold to replenish, the mod find out which type of merchant you're bartering with and select the basis amount accordingly.

Once we have the basis amount, we multiply it by the Gold Multiplier and this is where the different versions of the mod yield different results.

For example, Arcadia in Whiterun is an Apothecary. The basis amount is 500. If you use the 1x version, the mod will replenish 500 gold (500 x 1). If you use the 15x version, the mod will replenish 7500 gold (500 x 15).

On top of that, there's also a random amount of gold added. That random amount is between 0 and the "basis amount". Building on the previous example, the 15x version would yield anything between 7500 and 8000 gold (500 x 15 + random(0,500)).

It's possible to change the Gold Multiplier with the console. Simply use set TTRGoldMult to X where X is the multiplier you want.

Limitations
Unlimited Gold doesn't mean Unlimited Selling Price
To address the gold problem, all the mods I've seen go in the same way: they add a lot of gold to merchants. The unfortunate effect is you can sell 1 item for a disproportionate amount of gold. My mod address this problem by limiting the total amount of gold available, but replenish the merchant's gold to avoid waiting the usual 2 days or the need to find another merchant.

Investments and leveled gold have no effect on the gold added on the merchant
Including those would unbalance merchants' gold unnecessarily and would require a much more complex solution.

The gold on a merchant will never be greater than 20k
Technically speaking, it's impossible for a vanilla merchant to have 20K on itself. The only way this could ever happen is if a mod introduces a custom merchant with gold on himself. In that case, this mod caps the gold to 20K to avoid the merchant gold bug where the gold get stuck at 30k something and you receive nothing for things you sell. I chose the 20k value because I didn't want to get in the way of other mods too much. Normally, you'll never get near that amount of gold on a merchant. You can adjust this limit using the console command set TTRGoldMax to X.

A merchant that doesn't use the standard dialogue to barter with you will not benefit from this mod
You could ask the author to add the functionality to his mod or do it yourself. I include the sources for that reason. Normally, it should work out of the box as modders don't tend to stray too far when it comes to this aspect of the game.

Installation
Requirements
Latest version of Skyrim Special Edition (should work on normal Skyrim too, but not tested)

Install (auto)
For an automatic install without risk of errors, I suggest you use the NexusModManager

Install (manual)
For a manual install, extract the files from this mod and copy them to the appropriate folders

Compatibility
Pretty much compatible with anything. The only mods that can conflict with this mod are the ones modifying the barter menu structure. Since Skyrim's original launch, only Vendor Sale Delay - Gone did that and I integrated the change into this mod.

Known issues
Merchants enthralled by Miraak to build pillars in Solstheim will simply not work
The problem isn't easy to fix as they're not considered by the game as NPC, at least not by the console or the Papyrus engine. Since they're not NPCs, I can't replenish their gold. Fixing this would mean changing a couple things in the Dragonborn's main quest... Let's just say I wouldn't dare try to touch this with a ten foot pole, so I don't plan on fixing this. In any case, you can still find merchants in Solstheim that weren't enthralled and work flawlessly, use those instead.