Should I dry clean vintage clothes?    I have quite a few (at least 20) button and polo shirts from the 70s and a couple from the 60s. Most are polyester and cotton,  but one is velour.

   Should I take them to a dry cleaners, or should washing them gently be enough? The majority of then cost me $5 or less so is dry cleaning them a waste of money? I wear some of them quite often but I'd still like to know if there's a way to clean them while still preserving them. 

   Thanks.