Seriously, you tell the dude if you've modded the machine. He's buying something, and the ETHICAL thing to do is to tell him what has happened to it. Discluding something from the table is lying. You don't tiptoe around it.
If the neighbor wants to buy the whole computer, then that sounds like a pretty sweet deal to me. 400 bucks man
<b>I'm an unhyphenated American.</b>
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