ZQA297/30,
A LOT of operators do engine oil analysis, its a very cheap way of monitoring the condition of a very expensive engine. I have paid 180 bucks for an oil analysis.
Borescope inspections are routine, any maintenance facility will have a 4 grand Olympus borescope, again its a very cheap way of inspecting an expensive engine can be done on wing if need be and allows a visual without having to break the sections open with the time involved in the shop and often if you break a section open then you may have to perform an expensive and unneeded overhaul on disks and blades in that section.
It's understandable that perhaps non-aviation, non-pilots may have concerns through lack of knowledge, but for commercial pilots to have so little knowledge of how aircraft and their engines work and are maintained would be surprising.
Yet comparatively, is anyone that concerned about an aircraft that has been stored in a region less than 200 miles from a coastal area ?
Corrosion to blades (exacerbated by marine moisture) and disks is equally damaging (in different ways) to blades and disks, often the damage is enough to leave an engine subject to overhaul if a chemical bath and test cell run shows the damage more than superficial.