I'm looking into buying a preowned iPhone 5s. Some are with Rogers, others say Telus\Koodo. Will Koodo be able to unlock the Rogers one? If so for how much? The others say Telus or Koodo so the phone shouldn't need to be unlocked? I am on the $15 prepaid Koodo plan with my current phone if that makes any difference. My current phones sim card also will not fit in the iPhone 5s but I could simply buy a new sim card from Koodo right?