I bought the iPhone 6 plus 2 months ago directly from Apple - paid cash. My monthly plan is with Koodo. Will Koodo let me trade in my 6 plus for the regular iPhone 6? Will it cost me anything? I fine the 6 plus too big!! BTW... it's a 64 GB and has the otter box cover and is in 100% condition!!
They can look up trade value at the store. It will be worth quite a bit of money since it's a high value unit but they won't care about the Otterbox and it will still be lower than retail price of the 6. You might be better off selling it privately.
Just to let you know, the second-hand resale value of that phone is $800-900. Keep that in mind when entertaining any trade offers. Sure, they'll never come close to this sum, but I wouldn't trade this in for less than $600.