If you want the fastest, repeatable solo money right now, Cayo Perico remains the practical number one. After the cooldown and primary-target value tweaks introduced in recent title updates, a clean solo stealth run typically nets about 1.0-1.5 million GTA$ gross per finale depending on target and secondary loot, with realistic take-home per hour settling around 0.7-1.1 million GTA$ once you factor prep and the cooldown. Confirm your current cooldown and target values in-game, because Rockstar has adjusted them across updates.
For small crews, the Diamond Casino Heist is the volume king. With a competent duo or trio and the right approach, Gold averages put the team at roughly 2.2-2.9 million GTA$ gross per finale, and rare Diamonds event weeks can push higher. After crew cuts, a duo host can clear about 600k-900k GTA$ per run, translating to 1.0-1.6 million GTA$ per hour for the pair if you chain efficient preps and avoid alarms. Your exact numbers swing with vault contents, approach, NPC crew choices, and any current event modifiers.
Doomsday Heists pay chunky finales but lose on hourly efficiency because of heavy prep time. Act II is around the 950k-1.2 million GTA$ gross mark and Act III about 1.2-1.5 million GTA$ gross, but plan several hours of setups per cycle. Unless you specifically want the challenge or awards, Doomsday is more prestige than grind. The original Apartment Heists are great starters and award solid first-time completion bonuses, but their per-hour drops off compared to modern options: Fleeca is a quick 2-player intro, then Prison Break, Humane Labs, Series A, and Pacific Standard, which caps near 1.25 million GTA$ gross but bleeds cash on escape if sloppy.
Ranking for money per hour: 1) Cayo Perico solo for players who want independence and low hassle. 2) Diamond Casino for 2-3 player teams who can run silent approaches and reset quickly, especially on Gold and limited Diamonds weeks. 3) Doomsday Acts II/III for groups chasing big single payouts and challenge awards, not pure hourly grind. 4) Apartment Heists for beginners learning roles and banking the generous one-time first-completion bonuses.
Bottom line: If you play mostly solo, invest in the Kosatka and learn a fast stealth route for Cayo; when friends are on, swap to Diamond Casino with a practiced duo or trio. Use free roam money makers to bridge Cayo's cooldown and always check for weekly event modifiers that can swing vault contents and finale payouts.
