Shouser144, we are happy to hear you want to continue your loyalty by porting over your landline. It's important that we need to get you the best option and all needed information for you to port over your number successfully. Help is here. At this time, with our network upgrades, the Samsung Galaxy S4 is not able to be activated on our network. Here's more details regarding the change: https://www.verizonwireless.com/support/knowledge-base-218813/ Lamentamos este inconveniente.
We do have some really good deals on compatible devices. Click here: https://www.verizonwireless.com/deals-landing/
To answer your questions, I can assure you adding the line will not mess up anything with your S7. Also, it will be better to purchase one of our deals and port the number over instead of buying a prepay device from another carrier. You won't need a temporary number; however, it can take 4 - 24 hours to complete the process as long as the correct information is submitted when porting. Here's some frequently asked questions on landline porting: https://www.verizonwireless.com/support/local-number-portability-faqs/
I know I've provided a lot of information for your review, please let me know if you have any questions.
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