You can buy a fretless cheaper than a fretted of the same make/model simply because there is less demand. I’m with others that you shouldn’t dive in with an expensive bass when you can buy a decent fretless for relatively cheap. One of the biggest downsides to low cost basses is shoddy fret work, but that is not a thing with a fretless, although you don’t want a fretless neck with dips & dives.