As someone who has collected comics for over 30 years, I am often asked about bagging and boarding comic books. Yes, it can be expensive and time-consuming, but bagging and boarding your comics will give you the best chance of preserving your collection outside of having each comic slabbed.
I bag and board ever comic I purchase even if it is a freebie I picked up at an event like Free Comic Book Day. While it is a stretch, there is always a chance a new comic given out on FCBD might end up being a smash hit sometime down the road. Even through thousands of copies might have been given out for free, there is only a small percentage of collectors which will show the same concern and care for freebie comics as is shown for $50 issues.
Bags alone will help to keep moisture and insects away from your comic. Over time, though, stacking the comics or standing them up will take a toll on your collection. Stacking them will cause for pressure damage on the lowest issues in the stack and standing comics up will place pressure on the spines and cause them to buckle or separate from the binding. Bags and boards together give the best support for your collection.
People will often tell me that they do not bag or board their comics because of the price involved in keeping a collection secure. I never thought this argument made sense. A 10o pack of bags or boards can sometimes run $10 each. This is $0.02 a comic. If you are going to spend $4 on a new comic in the first place, spending an extra $0.02 to keep it secure is not a stretch. The difference can really come down the road if you go to sell you comic.
The New Mutants was one of my favorite titles when I was a teenager as the characters dealt with some of the same types of angst I was at the time. In the early part of 1991, the series was winding down and everyone knew there would only be a handful of issues left when issue #98 came out. Nobody knew that Deadpool, who was introduced in the issue, would turn out to be one of Marvel’s prime characters over the next twenty years. Anyone who spent the extra money to keep the comic they purchased for $1 back then is happy when they see copies selling at conventions for over $100.
If a comic is selling for $100 at near mint, it is not unreasonable to say one rated at 8.0 would sell for $15-$17 less. At a 7.0, the total value of the issue can drop by almost half. Isn’t the $0.02 worth keeping the value of a comic as high as possible?