Can I use a verizon iphone 4 with at&t pay as you go?

Is there any way to use iphone 4 with at&t pay as you go? I know there are unlocking tutorials etc. That you can use, but I want to be sure before I buy this used verizon iphone 4. Also do I have to be worried about getting a bad ESN if I'm unlocking it anyway? Any info is appreciated.

Verizon phones can't work on AT&T's network and vice-versa. It has nothing to do with locked vs.unlocked or prepaid or not; the problem is that AT&T uses GSM radio format to talk to their cell towers, but Verizon uses CDMA format. Those are two different formats which require different electronics inside the phones.

What this all means is that the *only* iPhone that *might* be able to work on AT&T pay as you go, is another GSM iPhone. And in the USA, I think AT&T is the only company that has iPhones that are GSM (I know Sprint is also CDMA, not GSM).

If you want to try this, here's a page that says how to do it (I have no idea if it really works):
http://appadvice.com/appnn/2011/05/convert-unused-iphone-pay-phone-jailbreaking-unlocking-required

P.S. Also, GSM phones require SIM cards, but CDMA phones don't use SIM cards. Just another reason why this won't work.