Quick tip: If your car gets submerged in water like this, the first thing to do is DON'T START THE CAR.
Have your mechanic drain and replace the engine oil and transmission/gear oil with the correct fluids first. After that, the car can be checked and started carefully to assess any electrical or mechanical issues.
Starting a water submerged car immediately can cause much more serious damage with changing the oil .
Really hope people don't have to spend unplanned money with this flood