Why corrosion is worth catching early
Salt laden air gets into a laptop through the same vents that cool it. It settles on the board and slowly attacks solder joints and connector pins. The early symptoms are not dramatic, which is exactly the problem: a port that works only at a certain angle, a machine that wakes up sometimes, a fan that runs when nothing is happening.
At that stage cleaning the board and re-seating or replacing connectors usually fixes it for a modest amount. Once corrosion has eaten through a track, the repair becomes board level or the board becomes a replacement.
If you live near the coast and your laptop has started behaving oddly rather than failing cleanly, that is worth a free diagnosis before it becomes a quote you do not want.