High storage
Cabinets or a continuous shelf run set in the idle band above wardrobes and doors — the most forgiving vertical move, working even in a standard 2.7 m flat with no structural loft. Reserved, by the reach rule, for rarely-touched things.
The idle band, shelved
A continuous high shelf the length of a room holds suitcases, archives and seasonal kit. Add a safe step as part of the design, and keep everyday items down low where you can reach them.