It depends on what you have. They like Rookie cards and more sought after uncommon rare cards. They are more than likely not interested in overproduced or junk wax era commons. I have seen some hand organized sets in the store, but they have been there a while.
We are interested in GOOD rookie cards that have at least a $25 value. If the cards are older than 1970, we are interested in more than just rookies. While we cannot look through a whole collection, we can evaluate a handful of cards (50-100 cards.) Remember: condition is everything!
The answer I tend to hear him give when I've been in there, is that it all depends on what you have.
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