If out of warranty and regardless of where you bought it I would price shop. You could try Bit's-N-Byte's over on 12th, I've had good luck there. Cellphone guy might but I've never been there.
Depends what's wrong with it, check with Zach in the cell phone area.
No, but if you bought it within the last 2 weeks and it began to malfunction then yes (they will most likely replace it for you). Or if you purchased a protection plan and it began to malfunction, then it is also covered. However, if you did not purchase the Amazon Fire HDX from Best Buy, then the chances of them fixing it are slim. It depends what needs to be fixed too, because sometimes the cost of fixing it is too similar to just buying a new one.
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