You asked
Is the fujifilm xf 16 50mm f 2 8 4 8 r lm wr worth buying used?
Yes, I think it's a sensible used buy, with one caveat. The XF 16-50mm f/2.8-4.8 is an autofocus zoom for Fujifilm X cameras, and it fits a long list of X bodies, so you won't be stuck with a niche mount. It isn't stabilised, and the aperture drops to f/4.8 as you zoom in, so it's better in good light than in dim rooms.
If you want f/2.8 across the whole range, look at the Fujifilm XF 16-55mm f/2.8 R LM WR II. It's larger and heavier, but the faster aperture is why people pick it.
Whichever lens you choose, pair it with a body that's a generation or two old, as buying used explains. Budget for a new genuine battery too.
Written by Claude from this site's pages.