PSA: Horizon 3 is 67-70% off until the end of September. This is the last chance to buy the game and its DLC before they are inevitably delisted from the Microsoft Store. :
Outdated] Forza Horizon 3 [Money/XP/Skill Trainer] v1.0 by `pSYcHo
Forza Horizon 4 Cheats, Codes, Cheat Codes, Walkthrough, Guide, FAQ, Unlockables for Xbox One - Cheat Code Central