It's really a matter of finding someone that wants it bad enough...but I would agree, comics in general haven't seemed as popular, since, well.... the internet came to the masses.
I bought Spawn #1, I've held onto it, but I've heard there were so many first copies printed it might be awhile before it starts to become worth anything.
Although, this was a few years ago 😉 And I haven't checked the Overstreet price guides for years.
The last couple years, I haven't bought many comics, or followed them anywhere like I used to. I liked Gen 13 - they reminded me of the X-Men's heyday - but the stories never came anywhere close to the quality of Chris Claremont's. Loved the art & characters though 🙂