Every General Store you add to your base increases your base's storage capacity by 50 units for storage of weapons, tanks and other objects.
Note that the storage capacity for your base is in actual fact unlimited. It is not necessary to have a storage module in order to store items. Your troops will gladly store junk in the halls, on beds, in the showers, the commander's office, etc.
However, in order for you to be able to transfer objects from transport ships or other bases into the base, or purchase new items, you will need more storage module space than what you actually own. If you have more items stored than your minimum storage space, you will no longer be able to transfer items into the base from ships and other bases, or purchase new items.
You can continue to construct new objects and bring home gear captured through tactical combat well beyond the storage limit.
For a list of item sizes and an explanation of how storage works, see Base Stores.
Construction Time: 10 days
Construction Cost: $150,000
Maintenance Cost: $5,000/month