Color DMD and LEDs (if you count that) is about the only thing that has personal value to me. Other mods, especially just the stuff you literally stick to a game, don't have any value to me so I'm not willing to pay anything "extra" for them and don't want to spend my time removing them and trying to sell them. Even LEDs are tough - I will "pay" for them to an extent. I only keep a few extras on hand so I usually just order them when I'm going to LED a game so I can understand adding 100 bucks-ish to the price, assuming I personally like how it looks. There is some value to me personally in the labor depending on the game. For example I bought a Baywatch that was 100% LED with Comets, exactly how I would have done it, and all the work was done - including dealing with the obnoxious Sega/DE stapled down GI sockets. In my head I was like ok I'd be in 120 bucks for the LEDs, plus my time and frustration, so I was totally fine with that "built into the price". For a game where it's a quick swap on the lights, I may value that less.

So to answer your question - it depends .

I'd 100% agree on toppers except the relatively cheap ones that shipped stock with the games and basically advertise the game, like the one I have on Space Shuttle, or the one that covers the High Speed beacon. That said, I think they look super neat but wouldn't pay anything crazy for them...I think I got a NOS Space Shuttle one for like $25 bucks? I have the topper for JD but just because the guy I got it from just threw it in anyway for me for free after I told him I didn't really want it. I can't fathom paying what people pay for like the toppers for modern games at several hundred a pop.