BTN is exploitable grinder: bets and calls with a very wide range preflop, then plays fit or fold postflop. I frequently call him light pre, then on the flop bet into him or bet when he checks and he folds.

Middle player is ultra-fish calling station.

Hero is BB with 3456

PREFLOP
UTG calls
UTG+1 calls
Fish calls
Next player calls
BTN pots
SB folds
Hero calls
UTG calls
Fish calls
Next player calls

FLOP (32BB) 23k
Hero checks
UTG+1 checks
Fish bets 9.5BB
Next player folds
BTN calls
Hero calls
UTG+1 folds

TURN (60.5BB) 23kA
Hero checks
Fish bets 3BB
BTN calls
Hero calls

RIVER (69.5BB) 23kAQ
Hero pots
Fish folds
BTN folds

I pot the river because fish frequently calls here and BTN will only call with a made hand otherwise he folds.

How do you play this to extract more value?

Raise turn, obviously. It doesn't have to be pot.

fold pre fold flop. after that turn is easy

I'd definitely fold pre, but I think peeling flop is good to that sizing.

On the turn leading small or check-raising small make sense. Calling turn and potting river seems just silly to me. I'd rather check river as played.

Thanks for the replies. I like the small raise (maybe to 9BB) on turn, then around 1/3 pot river line.

Believe you me, 3456 is hardly ever in my preflop calling range. I had 3 reasons for calling:

1. I was on an extreme heater winning 2/3 fliers. While I don't usually base my play heaters, in this case I was up 300BB and decided to play the rush.

2. Usually when that particular player on the BTN raises everyone folds. As stated, he is super easy to outplay postflop esp heads up.

3. The other players in the hand where all fish. If 2+ of them call, there was a good chance the pot could swell to 200BB+ by the river.

I this thinking reasonable?