no
Buy a verizon phone
Yes they have to let you keep your number now.
You can switch carriers all you want, of course, but you would need a Verizon phone to use on the Verizon network. If you have an unlocked phone, you would want to call and verify it with customer service. Their number is 1-800-922-0204, by the way.
Yes, you CAN keep a Verizon number if you switch to AT&T! You must speak to the porting department of both companies. AT&T's porting and activation center number is 888-898-7685.
Definately. I like Verizon though..you should switch. i did
Yes
If you wish to switch service providers - you need to contact Verizon and get your Port Authorization Code (PAC). Once you have your PAC - you contact your new supplier, and give them the code - so they can switch your number from Verizon. The only thing to be aware of is - Verizon can charge you for issuing the code (they would prefer you to stay with them !)
no
yes you can. i had it and made it prepaid
Both phones use a micro-SIM card, so provided they are both under Verizon, you should be able to move the SIM from one phone to another.
You cannot. Verizon = CDMA AT&T = GSM (network that houses the iPhone) CDMA and GSM are not compatable.