Since Playata in its greed is refusing to implement diamond spending confirmation, I wonder if I should play this game with a balance of zero diamonds? Not quite having my pointer in the right spot, I managed to click on the Hunter Instinct in the Boosts dialog and drop 19 diamonds when I had 57. I'm working on a Movie Voting Dickstarter task, so I'm not interested in best experience or cash at the moment. We've asked Playata to implement this check numerous times over the years. We must conclude that as a feature that would reduce their income, it is not in their best business interests to implement.
Of course, I'm already implementing a best personal practice and not spending money on this game, so in my case, it does foil their business practice.