^^^ this 100% when it comes to vintage instruments ^^^
That said, there are still a good amount of older players who aren't as 'hip' to the current market or spend no time on forums like this, where people are super into this stuff. For them, they just know they bought a bass around 1974 or sometime around then and want to sell it for a decent price. Sometimes people aren't out to screw other people, they just don't know or care about every detail of the instrument they want to sell. You just have to do the research, keep an open mind and open eyes, and feel out the seller and the situation.