You don't. You'll just have to have a leap of faith . pretty much the same as anything you order on line being unable to see the condition of the item first. Trust me as a father to 6 kids. I definitely am not wasting my time on here trying to rip off a total of 5$ worth of credits for all my adds combined
Anyway if this site is anything like eBay if there's an issue with a sale I'm sure you'd be able to complain to the site and they would deal with it accordingly. I am unsure as to what exact procedure is since I've only been on this for two weeks now