Minor note: It would be better to add the gold before all of the players buy it and then remove it. Otherwise, if someone normally doesn't have enough gold to buy it, they will get an increase in gold afterwards. (Gold doesn't go negative)
I'm on a page about incorrect corrections, and spent the better part of like two hours trying to get someone to understand that -5^2 = -25, not 25, and then that post had comments get reposted because that group is self sustaining, and that person was in turn trying to explain what I just explained to them. And I'm taking that as a victory