What Percentage Off Would You Expect to Discount For Open Box Amp with Blemish

The amp is also a discontinued model which I believe should be further discounted.  So how much off  on a $3200 amp is the question? I called the dealer with a few questions. I asked if the amp would be on sale for Memorial Day since it’s a discontinued model. The girl said they didn’t do many sales on this brand (I know they do) Anyway,  she looked and found an open box in warehouse. She knocked 12% off MSRP. Does that sound right? Or should there be more discount due to blemish?  I think the later. I’ve always thought 10-12% off to be the norm discount on prime products.I know this isn't set in stone. But what is "normal" ? Whats your thought? Thanks for your input