Don't feel guilty for jacking up the price for the winner if you were both sniping. He doesn't feel guilty for taking the keyboard away from you.
BTW, if you're buying a NIB Mini for $400, are you just storing it, or are you actually using it? As soon as you use it it's not NIB anymore, it's UIB and worth much less, right? Are you buying NIB because you want to use the hell out of it for the rest of your life?
Or do we acknowledge that NIB is a lie and it really just means "clean, functional, and comes with the original box"?