Thanks for the replies everyone! I am definitely used to cold weather camping as we have done it in our Travel Trailer but only where we had electric hookup so battery power was not an issue. Generally the low temps would be in the teens or twenties overnight.
To clarify... I don't think I would stay at the resort, rather we would head to a walmart or state park where running the genny overnight is not an issue. Its just during the day / evening while we are skiing that I would be all battery power.
Regarding the batteries, I was not implying "only 2", I was asking if they have at least 2. Just making sure that the battery that starts the motor would not be effected even if the house battery was drained.
Thanks again all!