Are any Susan B Anthony dollars valuable?

Are there any Susan B. Anthony dollars that hold significant value or are they all considered to be relatively common and not worth much more than their face value? Are there any specific years, mint marks, or conditions that make certain Susan B. Anthony dollars more valuable than others? If so, what are the key factors that collectors and investors look for when trying to determine the worth of these coins? Additionally, are there any resources or guides that can help individuals identify and assess the value of Susan B. Anthony dollars they may possess?