My favorite was when some redditor told me that "maybe 3d printing isn't for you" after I expressed some concerns. Pissed me off so much I ended up printing over 200 miniatures (so far).
I use cheap resin, it's roughly a dollar or two per mini. Gloves and supplies are cheap but add up over time. I haven't calculated it with any precision, but it's comfortably cheaper than buying them, and I can make small modifications to them.
I would assume electricity costs are minimal for resin printers. I haven't measured mine, but the only major power consumers in a resin printer are the Z axis motor and the UV LED. The UV LED isn't continuously on and the Z axis doesn't do a ton of movement. Compared to an FDM printer that is constantly running two heating elements and moving a heavy hotend all over the place, the power consumption should be a tiny fraction.