It is sad, I agree. Once I spent almost half year repairing a water damaged device, it was a horrible experience. The worst things are: 1. corroded vias between layers, especialy if it is 4 or more layer board, 2. corroded, unmeasurable capacitors and resistors, 3. corroded (black) copper pads, which are very hard to clean and solder, 4. corroded or totaly lost BGA pads.
I would say clean it and look better under microscope. Test the board. If you see some of the signs mentioned earlier, better just search for a new board.