Wait wait, so you guys are saying if you bought a 2nd hand phone off CL, meet at the Provider's store (Verizon/Sprint), have the provider test for clean ESN and TRANSFER the phone to the buyer's account that you could end up with a BAD ESN if the seller had outstanding bills in the future?
Wouldn't the Verizon/Sprint store just transfer the ESN to the new owner right then and there or is it tied to the old owner forever?
A phone that is tied to an account does not have a "clean" esn. You can't activate a used phone on a new account until it is no longer active. Whether it be the previous owner upgraded to a different phone or cancelled their service in good standing.