[The Godfather]

For people who want Verizon service and outside their lte coverage, the 4S is actually the better choice: unlocked iPhone will work in 3G areas when needed worldwide.
How does one purchase such thing from a known individual, while retaining the unlimited and perhaps changing the phone number?
The payout to that certain individual would be the fact that they would be free of their 2-year contract and able to buy a new iPhone 5 at a subsidized price. Is that a fair price, or should they pay for the favor?

[mduell]

The unlimited data is tied to the account holder, not the device.

[The Godfather]

Then the only option is to get the seller allow the buyer to make the monthly payments and hand the iPhone 4S to the buyer.
I am sure there is an option to change credit card auto-charge in the Verizon online account management website.
What it the ETF that a Verizon iPhone would be facing if he/she does not "transfer" his/her contract responsibilities in this way and wants an iPhone 5?