The Internet makes hunting for collectibles—or just about anything—faster and easier. Web-based shops and auction sites not only expand the selection far beyond a brick-and-mortar store, they also offer amazing deals. But as with all commerce, what you see isn't always what you get. And although buying from a major online retailer is relatively safe, dealing with untested sellers—through auction sites or what I'll call "flea-market" sites such as 1stdibs.com—can be risky.

Now, I don't mean to scare you offline, especially considering that 70 percent of eBay users are "highly satisfied" with their shopping experience, according to a 2007 Consumer Reports survey. I do, however, want you to slow down and weigh your options before clicking Buy Now.

Follow Suze's six rules to stay safe.