How Much Does Damage Affect Value?


I purchased a "mint" amp, cost roughly $1100. Well, packing was inadequate and the unit suffered corner damage on the faceplate during shipping. The damage is not a deal killer for me, but it is there. The unit was originally a 8/10, now I guess it would be a 6/10, though other than this blemish it is quite nice with next to no sign of wear. What would be a fair de-rate to the value?
smata67
Post removed 
IMO it would be difficult to resell the amplifier with the damage shown in the photos. Possibly its present retail value for resale is around $500.00. Your photos don't show the area of the box that was damaged in transit, if there is any damage.

The box that is shown is intended for transport from a manufacturer to a distributor/retailer in bulk on a pallet, not for shipping through a ground carrier with multiple hub transfers, conveyor belts and the potential for mishandling.
Bummer the part isn't available. I agree with most of what's been posted(outside of the smart a$$). But one factor hasn't been addressed: How much do you like the unit's sound/presentation? Can you bear the cosmetic flaw, to enjoy the amp? What's the amp worth to you?