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
I think the above suggestions are adequate fair and responsible... if no other recourse is available. ie., the cariier.

Everytime, and I do mean everytime, a carrier will submit it is the fault of poor packing. It's just what they do the majority of the time. it's like their default answer to any claim.

I even know of an occasion in which the carrier said it was due to poor packing, and the carrier did the packing! They failed to notice the checked box on the shipping bill where they had provided the service.

Carriers, I think, feel a package should be able to withstand a drop from a tenth story window right onto the street below.

Not trying to mitigate for the packer/seller, just some alternative thinking.
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.