Here in Australia there are mandated inspections on Cessna's for airworthiness and corrosion, called Supplemental Inspection Documents. I believe the FAA has them too? They are expensive and I have seen some very nice old Cessna's being sold off cheap due to their cost, or fear of what they might find.
The formerly called Cessna SID is now part of the ordinary Service Manual and valid for all Cessna aircraft of 1xx/2xx series produced up to 1986/87. There are a lot of myths around the costs of the inspection, but much of that is due to shops ripping off their customers and armageddon talkers with a lot of findings (which justifies the necessity). Yes, it is major work, but if you schedule the inspection parts with your usual maintenance the extra cost is far from what was said in some threads. If they find things, it can get expensive, but than it does have a reason ... From a friend I heard that his 172 inspection alone was around three and a half grand, only minor findings and about one grand repairs (saw ads from Czech, where they offer flat 2,700 Euros for the complete SID). Yes, it does add up, but the SID is not a major cost driver, at least for a 172 and up - different story for a 150, which may be worth 6 grands only anyways ...