my check engine light is on and the codes are P0712 P0700 and P0562.

What is your question?

Thw check engine light is always on, but the problem is intermittent.sometimes the car wont shift gears. I called a repair shop and told him the problem/codes and was told the solenoid pack is bad and it would cost $450.0 to replace. Is it possible that this could be something more simple like a bad sensor? Is this price reasonable for the Solenoid Pack?