Is this normal/due to humidity or a bad sign?

[81Wagon]

I'm considering buying a 300SD, but it's 100 miles away so I haven't gone to look at it in person yet. Interior and exterior look clean.

But Carfax tells me this car came from Louisiana (no flood damage reported to DMV but what's that worth?) and the picture the seller sent of the engine evinces some corrosion. Coming from a dry climate, I have no idea whether this is normal for an engine from a humid climate or whether it might have been submerged or something.

Any thoughts? I don't want to waste my time driving out to see it in person if it's not going to pass muster...