You might be sitting on a goldmine if you read and collected comic books in the 1970s. Comic book paper from that era was cheap and not made to last. Readers would cut coupons out of comics without a thought of conservation. Some titles had short print runs of special variant issues that are hard to find now.
There are also many pivotal first appearance issues that fly under the radar for many, even some collectors. The first appearances of Thanos and Swamp Thing occur in comics with such run-of-the-mill and average covers that it is hard to believe. It would be easy to overlook the importance or value of the comic if you didn’t already know.