Before designing a cage plan, settle three things, or the cage will not match the warehouse. First, by plant structure. Clear height under beams sets how high racks and stacks go; column and beam positions affect layout; floor load and flatness decide heavy-rack feasibility; fire and lighting positions are avoided upfront. Second, by cargo traits. Outer dimensions directly drive cage spec choice; cargo weight drives strength rating; whether the unit is a pallet, cage, or single item drives the container. Estimate total slots with two years' growth in mind, not today's volume. Third, balance accessibility against storage density. High density costs easy access; easy access costs density. FIFO and slot numbering are settled at the planning stage. These figures come from storage-system analysis, or we can advise before design.