How much storage do you need? Use our self-storage size guide to determine which storage unit size best suits your personal or business storage requirements. 3m² 9m² 12m² 16m² 33m² Small unit (3m²) Easily fits a computer, a desk and six storage boxes. Medium unit (9m²) Stores packing boxes, a small desk and a chair. Large unit (12m²) Accommodates the contents of a one-bedroom apartment. Extra large unit (16m²) Big enough to store the contents of a one- to two-bedroom home. Mega unit (33m²) Perfect for storing excess stock or the contents of a family home.