The biggest factor is NJ doesn't charge any tax
on EVs! Unfortunately that trick only works in NJ.
That said, it's rather easy to get a lease on a $53k i3 that's less than say a Bolt or a Leaf even though the MSRP is much higher. I managed to get into a 2017 REx in February for $200/mo with only $600 in fees out the door. I did own a BMW in the last 12 months (also an i3) so I got the $2k rebate for that, but that was the only YMMW about my deal. No state incentives here!
I think there are very few scenarios where it makes sense to buy a used i3 right now considering you can get a new one for less or the same total spend, in most circumstances.