Default T-Mobile question

would anyone know if say my cousins galaxy s3 won't work anymore and he got a new one, would they take his broken s3? I really wanted his when he upgraded, since T-Mobile does not so two year contracts they can't take it now right?
"Oh, you can't help that,' said the Cat: 'we're all mad here. I'm mad. You're mad.'
"How do you know I'm mad?' said Alice.
"You must be,' said the Cat, 'or you wouldn't have come here."

Motorola Moto X
Stock KitKat 4.4.4 XT1060
Samsung Galaxy Tab 2 10.1
Rom: Cyanogemod 11 (4.4.4) P5113

Asus Nexus 7
Stock (4.4.4) Broken Digitizer, any recommendations?
Both Stopped turning on for no reason
Nikon Coolpix s800c
Stock Gingerbread (2.3.3)