Another simple one. Invader Zim has always been all over Hot Topic stores. So it would make sense that they would carry an exclusive. So here is the idea:
You can order the Invader Zim #1 Hot Topic Variant straight from the site. They will cost you just over $4. (If you live close to a store you cam check to see if they have copies that haven’t been bent all up.) You can have the books shipped to store to save on shipping (but that does risk the books being touched by staff and bent.)
Now the flip:
The Invader Zim #1 Hot Topic Variant has been steadily selling for over $20. Some as high as $34, but most in the $20 range. Seems pretty simple. Grab a few, sell one and you have made your money back. Everything else is house money.