I received a $500 Best Buy gift card and would like to purchase Samsung S3 phone on Verizon. I am currently using a DroidRazrMaxx but my upgrade is not until 9/27/13. How much would Best Buy charge me for the phone? I see they have $699 on their site but WOULD i pay LESS SINCE i AM EXTENDING MY VERIZON CONTRACT 2 more years? Please let me know. Thanks.