I have been using a 5c for the last few years and it is finally starting to show its age and act up. I am also about to start a new job and have been told that a newer phone with a bigger screen would be very helpful so I am looking at getting a used or refurbished 6 Plus or 6S Plus. I don't take too many pics or use a lot of apps so I am trying to keep costs down and go with the 16gb until my budget will allow an upgrade. Can anyone tell me the big differences I will notice between the 6 Plus and the 6S plus? Also, if anyone can direct me to the best online outlet to get a used or refurbished phone would be great. I am hoping to not have to spend much over $400 if I have to. Thanks very much in advance!