My very few is a relative term. Take a look on Ebay today-I did. There is a trek steel lugged -true temper I think-with no bids at $199 with Shimano 600 components. It might fetch $300, but it is much more valuable better than the average 20 yo steel lugged trek..
For 20 year old lugged steel treks you will have 10-20 going for under $300 for everyone going for over $300.Ebay "sells" the best treks and the average trek there-20 yo-wil be under $300.
Show me otherwise. Do a search of old trek 531 listings-they are the cream of the crop-many are under $300. There are many old treks of that vintage that sure as heck aren't 531.
I'm not saying they aren't nice bikes-they are bargains,but folks here tend to be collectors who overestimate the worth of their bikes(except when they are selling of course).
Luck,
Charlie