Crowdfunding is one of the newer financing options available. At its most basic level, crowdfunding is asking a group of like-minded persons to back you. In essence, you tell them "I have this cool idea for a new way to sell manga on eBay, but I need a little cash to get it started". In return for their support (money), you reward backers with different incentives. For $5.00 you may give them a shout-out on your homepage or a free digital download. For $25.00 you may offer them a first edition of a new manga. For $250 you could offer them a hand-signed poster from a semi-famous artist. And for $2500 the reward could be an invitation to the online opening of your new store, or maybe you could offer to feature the backer's face somewhere in your store's graphics.
The most successful crowdfunding campaign to date was the Veronica Mars Kickstarter in 2013. Producers raised nearly six million dollars from 91,000 backers who couldn't get enough of the TV series. $25 backers were rewarded with a digital download of the movie, $200 backers received a movie poster hand-signed by the cast, and one lucky $10,000 backer received a speaking role in the movie.
In effect, crowdfunding is the coming together of people and an idea. It's a collaboration to make something happen.
For eBay sellers it's a tougher sell because in most cases you're raising money for a commercial product with just one purpose in mind - to make more money. So if you intend to attract backers, you need to craft one hell of a story.