The phrase "budget buster" refers to something that costs more money than was originally planned or expected. It can put a strain on someone's budget or financial plan. Full definition
One of the biggest budget busters can be the supermarket. (creditdonkey.com)
The Wisconsin import, an instrumental figure in the state's redesign of its costly Medicaid system, appeared in a video blasted out by Cuomo's Twitter account on Tuesday evening calling the plan backed a Reps. Chris Collins and John Faso as a «war on New York» and a «budget buster for the state.» (nystateofpolitics.com)