I have a bunch of stuff I've bought used (in great shape) with previous owner's markings.
I like when future sellers engrave their tools.
It creates a buyers market for me because most people aren't willing to pay a decent price when someone else's initials are on them.
Although I've read on here that some people automatically assume that used tools that are engraved are stolen.
I disagree. If your name is, oh let's say John Smith, and the wrench set you're selling me has "JS" etched in them, I'll buy them and sleep fine tonight.
Then again if some sketchy character in an alley is selling them, I'd pass.
But, truth be told, I don't buy much of anything from sketchy characters in an alley.