As far as whether it's due for maintenance, that depends entirely on how much maintenance the prior owner has done. Just because it's 42 years old doesn't mean it's in need of maintenance, if the prior owner has taken excellent care of it.
True enough. I have seen a Pearson Vanguard (even older model than the Wanderer) that was pristine and gorgeous, you had the sense nothing had been left unattended, functional or cosmetic. They wanted a fair bit more than $5K for it, but it was probably worth every penny