How simple can I keep it?

I didn’t want something too complicated, so this is version 1.

Features:

• Single width air bed on a custom made frame to have storage underneath
• Water in a jerrycan
• Insulation with rock wool
• Place to hang clothes
• Space for my bike, but ski season is starting
• No ventilation (can I just keep doors ajar? Maybe)

Pictures of the building phase here: