I am not sure the rules specify. But, our house rule is always, if you have the information and can remember it, it is not hidden. Money is purely a scoring mechanism and if you wanted to keep track of what everyone had, you could easily do this. so, why hide it? In theory, you could have a score track for this game and some players use the score pad that is out on the geek. So, again I would say there was no intent to keep money hidden in this game.