[Bob Landry]

You can add a 20A additional service, run it from the pedestal's 20A outlet, with a breaker dedicated to the 3rd unit. That's what I did with my Outback. It might void your warranty but maybe not if the dealer did the installation. I got tired of resetting breakers and added a second 30A service along with a 20A service strictly to run space heaters in cold weather. I requires some electrical knowledge if you do it yourself, but I'm in the marine business and I deal with shore power all the time.