My house sits at 2,620 meters (8,596 Ft).
The greenhouse is 20' long and 14' wide and is carved into the mountain. It has 2 full solid walls, one mostly window and one with a little strip of window. The greenhouse floor is covered with thick clay slabs, so that keeps the humidity at over 80% all the time and there is a lot of air movement.
I wish it would get more sun, but the greenhouse was built before my neigbor's house and now it shields a lot of light, specially after 12 or 1 pm.
The greenhouse is intermediate, but the back tends to be a little warmer and the front (close to the door) is the coolest, so the all the neps sit in the same greenhouse (along with all my orquids). On very cold nights (3 - 7° C or 37 - 45°F) I put a heater for the lowland plants. The cold side goes down to 13° (55°F) or around that.
In a few months, when we start having constant rain (it's now the dry season) most of the highlanders will be taken out of the greenhouse.