Parts? Manufacturing? Shipping? Labour? Storage? Distribution? There's more to a part than the cost. Now whether or not what they're charging is over the top, then I doubt you'll find much disagreement; however, the GP doesn't say how the damage happened. I don't know of a single vendor that will cover accidental damages on a screen, and no-one is responsible other than the party that caused the damage. Also, late 2020 MBA (M1) goes for $465, with ~$30 for the parts, ~$15 for shipping.

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