I was actually surprised when I saw this but ":cost" would be really helpful. It would simply show what the current cost of the building/upgrade is. I actually need this since i'm having it so you can buy a building which will give you one room. Doesn't give you a room per second, just gives you a room. Perhaps I could make a button that would look like a building button but either way, ":cost" would be helpful. If I had a building named "Portal" which would cost 100 boxes, and I wanted to maybe put it's price in the description. I would do "portal:cost".