Right now, if you upgrade your entire fleet of ships, it does not display the costs of the operation, meaning you (well, I 
) often found yourself in bankruptcy. There's no way of knowing how much money it will cost and compare it to your credit stash, nor will the game display a warning like "Warning: the operation will cost 2500 while you only have 2200 credits. Do you want to proceed?".
Shouldn't there be some kind of warning like that? Or at least a display of the costs?
