1. Diamond Casino Heist -R$10 million. The Diamond Casino Heist is the most profitable but also the most demanding heist in GTA V as it requires at least two players and meticulous planning. To carry out this heist, players need to purchase an Arcade from Lester through the Maze Bank Foreclosures website.1) Diamond Casino Heist\n\n The Diamond Casino Heist is the highest-paying mission in GTA Online.
