I read your comment and it said Take item on link. This would be something to start on but do not worry too much about it, alex. I had mainly money used on links. The only other time was the plane ticket. Since you have variables which can be used as money, this 'take item on link' would not be top priority.
What you should add is having variables being shown in the inventory. If the author selects to have them seen, then when the players opens his inventory, he can see what values correspond to each variable, and the author can select certain variables instead of all or nothing as well.