The return period is 14 days, not 14 days or longer while we determine the service quality at your home. I guess I am at a loss why you would renew your contract if you were having service issues at your home AND service in that location is important to you????
It is EXTREMELY doubtful you will be able to get a refund on your phone if you are outside the 14 day return period. You may want to look into selling the phone on a site such as swappa.com where you would be able to recoup at least a major portion of the cost of the phone AND any ETF you will incur by leaving Verizon.
If you have broadband internet in your home, have you considered purchasing a network extenter?