Probably can get a deal on rentals if you do so for 6 days, check out
This place is on the way from the airport to VN, and has discounts for more than one day -
http://www.masski.cl/arriendo-ski-sn...ki-y-snowboard
These guys have backcountry gear, bring your own boots -
https://sherpalife.cl/rental/equipo-de-randonee
OR
https://www.kladventure.com/ski-rental/
http://www.skitotal.cl/skirental?gcl...e40RoC6w3w_wcB
http://www.daski.cl/rental-ski-bike/
Good luck!