@Drachmor @RangerOne
Just off the top of my head
For main stat, base can start at 20 (race dependant)
+8 level ups
+8 tome
+14-15 enhancement bonus
+6-7 Insightful bonus
+3 quality bonus
+4 artifact bonus
+4 profane bonus
+2 exceptional bonus
+2 festive bonus
+2 guild bonus
+2 completionist
+2 racial completionist
+1-5 racial past lives depending on the stat
up to +17 sentient weapon (filigrees including raid/double filigrees that give +2 instead of +1... 10 slots from weapon, 5 slots from Myth Drannor minor artifact... not every stat has 2 raid filigrees for them, but every stat does have at least one)
+2 Yugo pots
+2 Remnant/Store pots
+2-4 Alchemical Bonus
+2 Competence from Bard Songs
+2 reaper helm
That's up to 113 (or as low as 88 with the lower bonuses and no sentience, 86 if you start at 18... subtract 8 more for non-main stat not getting the level ups bringing it down to 78)
Then you have your racial and class trees that can give more (up to +4 capstone, usually +2 from the tree itself, and some give even more in cores as well)
Then you have Epic Destinies which can give more (primal avatar +2 to all physical or all mental stats for example)
Then you have Reaper Trees which can give +5 str or dex, +5 int or wis or cha, and +5 con
Specific abilities can also get a Psionic bonus +6 to +8
Specific abilities can also get a Moral bonus +2 to +5
Specific abilities can also get a Size bonus +2 (just strength iirc)
Some trees/races give bonus abilities scores while an action boost is active
I'm not sure the bonus type of the Enhanced Bloodrage effect from some items, but that's another potential +8 to con and strength
TBH Str and Con are probably the easiest to get huge bonuses to. I recently did an item swap farm to be able to get 80 in every stat for the optional chest in Threats Old and New on a single character. This character is a warlock, so charisma based. Item Swapping for Wisdom was the hardest to get, while strength was hilariously easy to get)
edit: and if you get lucky, there is a cursed card effect that also boosts your stats for a potential +2 fortune bonus as well