We have read all your requirments and tried to design something for you.
At the ground floor we predicted double high bed, as you like it ( examples pictures).
Ground floor is completed with the fireplace for heating and toilet.Next to the bed is shelves which can be used for books or similar things and at the both bed si same situation.
At the floor is clasical sleaping area with the high which is enough for sleeping comfort.
Exterioror design is steel in combination with the wood, and that is the cheapest and for folding and unfolding.
We have uploaded tho version of structure and materials.
We tried to fulfill your requirements, hope uou will like it, we are at your disposal and at the end if you like it our design solution,
All the best.
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