Cost an Arm and a Leg

Something that is very expensive

Eye Candy

Something or someone that is attractive to look at but not necessarily substantial

Paddle Your Own Canoe

To be independent and self-reliant

Go Bananas

To become very excited, angry, or crazy

Sky Is the Limit

There is no upper limit to what can be achieved

Catch Someone with Their Pants Down

To discover someone in an embarrassing situation