Used mostly for me too. Most of my used toys (bikes, cars, houses, guitars), I know it can be fixed if need be. Typically, I shoot for 30% of retail.
For electronics, it's new for me though. There may be subtle weirdness of returned electronics that don't show up immediately. I encountered one about 12 years ago with a used laptop and haven't done that again. Having the replacement warranty is worth it. That said, I used to grab used laptops that were meant for discard from a former employer for experiments: it was a win for both of us.
Another exception has been my last two skis. Got some premium skis, new unused, for around 60% of retail. Couldn't believe that deals. Can't believe their preformance.
Another exception has a new carbon full suspension MTB at half retail.
Hmm... My tennis racquets have been always new, but again at steep discounts. Usually very difficult to find what I want at a deal even used.
What can I say, being frugal is good. There's something left for other things.