This is a late reply, but I got my V1 for $500 with only 26 miles on it. Just passed 800 miles on it and still on the Vega!
IMO getting another Onewheel for $500 is a STEAL. Especially if you'd want it as a secondary board for friends to ride. Just gotta be patient enough to find those really good deals.
Currently looking to get a lower mileage (<200) XR for $1000. It'll take time, but I've seen them around