[dbpatterson]

You could give them 15 days free use, and only charge it after that... there is a risk that the charge doesn't go through (in which case you've given a couple weeks free service - big deal), but otherwise, you've just made it much less useful for card testing (to the point that they certainly won't use your site).

[msandford]

Yeah, that's all of the upside and none of the downside really. Introducing ANY kind of delay between taking the order and charging the card will just about eliminate these kinds of fraudulent transactions.

[markbnj]

Yep, this makes a lot of sense.