We have an issue with people tricking other players to click signs to drain their balance, if you can add a check for if the price they are paying on the sign is more than X in the config, this would require a conformation to pop up to confirm the sale.

I suggest popping up a book with a [buy] and [cancel] this way it's extremely obvious and in their face, we can also include in the book exactly what they are buying and for how much.

This is along the lines of #109 and will be tracked there.