Generally Sony sets the price that any retailer can sell their products for. Any retailer that violates that, runs the risk of Sony saying they will not allow them to sell their products anymore.
However, there are some places that deal in used games and game systems. Those would be your only real hope. Expect to need a new battery with any used PSP you may buy.
could anyone told me that, where I can buy a psp which cheaper than sony shop?

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