Just downhill from the ski slopes, the spruced-up Refugio Teski offers unparalleled access to the mountain. It's not always professionally run, but it's a spectacular spot to stay as you can have the outstanding views of Lago Llanquihue and the surrounding mountains all to yourself once the tourist buses depart in the late afternoon.
With 24 hours' notice, rent out a mountainside hot tub (CH$40,000 for three hours, including a pisco sour and finger food) at sunset and make a night of it.