Whether you’re the type of somebody who upgrades their phone each year, or somebody who holds on to their phone to get the last drop of worth out of it, you’ll discover that there is nonstop someone who is keen to sell your old iPhone. The problem, though, is describing how much your old phone is worth. You could discover yourself overestimating the value of a phone that’s humbly a couple of years old, or perhaps thinking that a primary model of a no-longer general brand isn’t worth much. Global Gartner research proposes that 64% of the phones we buy are reused by somebody else, with most of those going to a new holder through private resale. Last year, global sales of second-hand phones produced $7 Billion in proceeds and on sites like SellTheMobile UK, iPhone sales alone surpassed $14 million. Actually, Gumtree saw an exponential increase in the number…