The phrase "money pit" refers to a situation or project that constantly requires a lot of money to maintain or complete, leading to financial difficulties or losses. Full definition
One of my favorite stores in the WORLD and a huge money pit for me! (lynzyandco.com)
Those issues can be used as bargaining chips to bring down the prices of their would - be homes — or even lead them to walk away from money pit purchases. (realtor.com)