Bank

This building daesn't produce any in-game currency, but it helps you to swap any in-game $ currency to another. This allows you to control all the $ in-game curriencies in balance to have more stable economic on your account.

Even if this building doesn't produce any currency you see the value it gives to gamers. To swap one in-game currency to another you will need to pay small $fees ( also in in-game currency )