chequeraise

Ac means he is not checking back with Ahi flush. I think generally most flushes that check back are the ones with some showdown value compared to say 45cc, so when he bets the Ac I think his range is really much more weighted towards Ax or medium-ish equity hands that didnt want to get C/R.

I think check calling and check raising seem both fine with some frequency. I think my default is def C/R. With a delayed C/R I dont think you necessarily rep a too small range either for him to only nit-call you.

If he's checking back stuff like T weak kicker or 8 medium kicker you probably only get 1 street of value out of it anyway so you can just bet river if turn goes check check.

If the reg is isolating reasonably wide (which is very likely) this looks like shove. It's only 5 handed as well.

If the reg opens we would 3bet shove as well right, again assuming he is opening reasonably wide (aka not a mega nit).

Shove. Lots of cards can kill your action on river and you are OOP so he will check back a shit ton, you would have to donk rivers to get max value which will be super awkward.

The problem is the recreational player. He deposits 50€ and plays and loses 10€, then he has to go dinner with his wife. After he comes back, he can no longer play at the €50NL since he only has 40€. Yet being forced to go 20€NL will feel as much as a defeat since his memory of the 50€NL and his 10€ loss there is still fresh. At 20€NL it will feel much more impossible/harder to win that back and thats exactly what he wants.

Anyway with a kind of bad vibe already he shrugs and plays 20€NL, after a couple of hours he loses and he only now has 3€ left.
There are no 3€NL tables, he can't join the 5€NL tables, he is forced to withdraw or re-deposit. At this point he will leave RunItOnce forever and return back to his favorite EU site.

Have we calculated the EV of 3betting turn compared to calling?

I know that most of his draws will fold to a 3bet, but against this type of player any made hand that raised for value will almost never fold. We have like 90% equity against his 3bet calling range.

Against his check raise range, I would say we have around 85% equity overall, but we will not be able to get the money in on a lot of rivers.

His raising range on the turn is probably very skewed towards bluffs, like you mentioned, bluffs could be as much as 80% of his range.

So if we raise he will continue 20% of the time, and we win 90000$ when we 3bet and get it in.
If we call, and he bet river and we raise, he will fold 85% of the time and he will have us beat around 15% of the time. I guess we win lets say optimisticly around 20000$ 85% of the time.

Am I completely miscalculating this or is the EV of 3betting turn not that insanely far apart from calling turn, or maybe even slightly more +EV?

With 10bb I'm pretty happy about jamming JTs pre here.