Absolutely. The key is to preserve their condition. The best players have the highest value cards. Wait to sell the best players until they reach the Hall of Fame.
There are many baseball cards from 1991 that are valuable. It depends on which players you have and what the player is doing now. Even players who are not active still have value in their cards.
It is difficult to evaluate the estimated worth of your collection because of the lack of details. How many cards do you have? How many rookies? Which brand of publisher?
