%200 run. Complete everything that is on the SOCIAL CLUB checklist.

69/69 Missions 61/61 Hobbies and Pastimes 58/58 Strangers and Freaks 60/60 Random Events (Simeon's is only available before the Jewel Store Heist) 30/30 Misc EDIT: This should also include every Singleplayer achievement except "A New Perspective" and all of the Rockstar Editor Achievements.

Currently doing this on a casual playthrough and it's really fun. Same rules as 100% would apply.