On the “Buy a warehouse item” page Weight and Space are being calculated incorrectly
For example, 1 Leather weights 1.71kg and takes around 0.002m3 (0m3 on a screenshot, can also theoretically be seen as a bug).
So 1000 items should weight around 1710kg and take around 3m3.
Calculations on the “Buy a warehouse item” page are vastly different
When you buy an item and have it in your storage or load the item in a plane, the weight and space are calculated correctly again.