Steps to reproduce:
-Simulate a full ship with modules
If you click “fit all” you get a message you are missing the hull or any of the modules.
-Buy the hull
Same message
-Click buy all on the right
-Set the number of item to buy for the hull to zero
-Click buy
The game buys a second hull anyway.
I know it is possible somehow for it to make a “buy all” list for the missing modules/hulls considering your current assets clicking fit all, but i can’t reproduce this behavior. Maybe if you’re inside the hull already. I’m not testing this, lost enough money as it is.
To use the feature “Fit All” you actually need to sit in the hull.
The game assumes all items on the “Multi buy” list has a number equal to or greater than 1. setting quantity to “0” will still be counted as a “1” (as it’s still present on list), you’d have to remove it from the list if you do not want it bought.