Some occasional problems with the ballast/centerboard that needed attention; but considering some of these boats are now 32 years old, some repairs are to be expected.
Sure, some problems may be caused by previous owners who failed to properly bed deck fittings or let a rudder sit out in the rain all winter but that is to be expected.
What is amazing on these older boats is how structurally sound they are. No cracking, no delaminations, no soft spots.
Quality counts.
Bob
Which reminds me of a question I've been wanting to ask: my M15 is, I think, a 1985. It spent its first nine years on a trailer in my driveway in Fresno, covered with a tarp in the winter, next ten stored in my garage in Fresno, then the last three has been in Washington. Hence the question: I have it stored under a tarp. No garage. Salt air. Should I be doing anything to keep it in good shape? It saw salt water on occasion before but except for a few weeks, was never stored in salt air. It has the old centerboard but so far no problem, to my knowledge. Bobbie