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ASAP prices will tank they day the announce the iPhone 7 do not wait even 1 more Day. iPhones become worthless fast. I have an iPhone 5s 64GB mint condition no one wants it even for $100.

My iPhone 6 16GB did sell for $450 right before the 6s came out. That was good.
Best Buy and other retailers usually have promo to trade in (currently lowest iPhone accepted is iPhone 5). But to trade in a 4 plus year iPhone in any condition and they give u $200 gift card.

Just wait for trade in promo for financing plans if you have more than 2 year old phones.
 
I've been wondering this myself; some sites have estimated around £400 for the iPhone 6s Plus 64GB.

It depends on what Apple announce in September; if it's worth upgrading try and lock in an offer with one of the many trade-in companies if you're lucky enough (sometimes you get 14 days' before the offer price drops) to get the new iPhone come launch day.
 
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