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You do not have to apply their opinions but it is sure good to know them.
Generally, if it is an older boat (how much older exactly?) then she has probably had all fittings replaced at least once. Unless she is a marina queen and that's the use you have planned for her.
Chainplates can last well. If they look OK you may consider pulling one out and inspecting for corrosion
. Much depends on how much inspection
you can do while they are in.