Suppose Isabella decides to take a trip to Mississippi. Which result would be a cost?

 - Isabella will save some money. Plane tickets for Isabella to get to Mississippi are less expensive than tickets to Montana.
 - Isabella will give up the chance to go to Montana. She would have enjoyed a trip to Montana more than Mississippi.
This result is a cost. It involves giving up or spending something that Isabella wants or needs:
Isabella will give up the chance to go to Montana. She would have enjoyed a trip to Montana more than Mississippi.