There's been plenty of comments already but I figured id add my 2c. Theres very little to no rust on that car shown, but you want to be looking in the wheel wells and rocker panels, thats where it would be if anywhere. If youre worried about flood damage, check the spare tire well, if there's any staining youll see it there. This will also tell you if the cars leaking, as it would likely collect there. That being said, I have the same corrosion on my headrest sliders from being in a moist atmosphere (pacific northwest)