Enders are built with some less than amazing parts. The extruder comes to mind. After 8 months, mine cracked just enough to make a problem and resembled a partial clog somewhere.
For a small price difference (you decide what ‘small’ means), I’d just pick up the new machine because the vendor probably has support and creality has done a good job supporting the machine for me. Assembly should take less than 30 minutes, as the preassembly is very well planned. I think you just screw together 4 subassemblies or something like that.
Beyond a small price difference, the used machine might make sense, and plenty of us here have one so you’ll be able to get lots of support if you need troubleshooting (i really can’t overstate just how awesome the forum members here are…absolutely amazing crew). Use it as is, or use it to print parts for a better machine, then scavenge parts from it for a build or resell it.
I’m turning my old ender into a corexy by borrowing parts from several other machines, but mostly because people out here don’t seem to want to pay fair prices for anything.