I'm all for setting your own prices. It's your item to sell. Afterall, if you price too high, who cares? The only person you're hurting is yourself since no one will pay for your item at that price. But, that's the point. Folks here (albeit, kinda harshly, but it's the internet. you've got to have thick skin) are trying to help you find a reasonable price to sell your item for. Pretty much no one will pay nearly full price for such a high wear item, that's not in the best of shape, when they can get a brand new part for just a little more money.
But, if you want to compare prices for used items out on the market, check out these two ads. Both ads are offering both the pressure plate and the clutch plate for only $169 + $21 shipping.
Porsche Boxster clutch 97-99 used | eBay
Porsche Boxster clutch 97-99 used | eBay
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