hand 1:

Looks good .cant see anything wrong here.

hand 2: I would have re-raised him when he raised you on the flop ..id have made it 650-700. Or even consider a push here.

hand 3: wtf ? ..weird hand, not sure why he would bet so much..this one comes down to reads, but im pretty sure its a fold 9 times out of 10.

hand 4: Definitely re-raise the river..make it 500ish.