No matter what it is—a pair of jeans, a car or even a house—in that moment when an object becomes your property, it undergoes a transformation.
Because you chose it and you associate it with yourself, its value is immediately increased (Morewedge et al., 2009). If someone offers to buy it from you, the chances are you want to charge much more than they are prepared to pay.
That is a cognitive bias called 'the endowment effect'.
It's the reason that some people have lofts, garages and storage...
