Best non-mod, non-"cheat" way to 10,000,000 gold?

[Murphy's Lawyer]

If I wanted to legitmately earn 10,000,000 gold by playing vanilla and not just using a mod or workshop or something, whats the best farm?

does better gold spawn in newgame+ mode?

[Zelph]

By going through the game, you get roughly 1-3 million from my understanding, and you get lots more at later levels. By going through it a second time, you might hit 10 mil.

[Lantadyme]

this also selling all yellows and it takes literally no time if your using mapworks

[Phaper]

Tank gold find equipment on an Easy character, and have a max level Barter spell.

I would guess Tarroch's Tomb, Mapworks, or Phase Beast Farming for location.

[Val]

1) Difficulty = casual. Optionally check which classes have the best %more gold uniques and start with the right one. Some of them may require plenty of gambling to get though (a setback).
2) Barter + Treasure Hunter passives for yourself. Treasure Hunter for your pet. Optional Animal Handling for both.
3) Optimize your gear for %more gold. Socket everything with 5-6% lucky coins (farm crypt, temple or dragon mapworks secrets), optionally try to get some Nephanic Skulls. A dozen of them will speed you up a lot.
4) You can try to invest into Luck enchanter, but I would be cautious about that in your place. Heck, in your place I wouldn't bother getting this achievement fairly.