How does a bad ESN work? (Blacklisted)?

I have an iPhone 4 with a prepaid sim card and I'm trying to buy an iPhone 5 online, but it might have a bad ESN or could be blacklisted. If I did get the phone, could I put my current ATT prepaid sim card into the slot and it work?

Yes
Work NO, the IP5 is NOT even an iPod Touch

Its called bartering the ONLY beneficiary is the seller.
I was going to say Charity, but I doubt your money will be used for a good cause

NO, that is what Blacklisted means dude. That is why blacklisted phones are so cheap, they are useless as phones.