The .Text member of a label is in String format, so to subtract from that you'd have to convert the String to an int, subtract, then convert back to a String.
It's much more convenient to store the amount of money in a global variable and update the label text each time it changes.
Open the Global variables pane and create an int, name "player_money", initial value 1000 or whatever the player starts out with.
Then use a function that'll change the value and update the label:
[code]bool ChangePlayerMoney(int amount) {
if (player_money + amount < 0) return false;
player_money += amount;
lblMoney.Text = String.Format("Total money: $%d", player_money);
return true;
}[/code]
Now you can do this:
[code] // player chose to drill
if (ChangePlayerMoney(-100)) {
// drill hole, etc.
}
else Display("You can't afford that!");[/code]
