it will cost you
it/that will cost (one)
1. Something will cost a lot more money, especially compared to a cheaper or simpler option. You can opt to rent a larger van instead of the sedan, but it will cost you. A: "Jane and Joe want to upgrade their tickets to first-class." B: "There's still time to do it, but that'll cost them. Are they sure it's worth it?"
2. Something will have a negative impact on one's performance or chance of success. A: "Uh oh, the quarterback just fumbled the ball on his own 20 yard line!" B: "Ouch, that'll cost them big time. They really can't afford to give up any more points this late in the game." You can try and fluff up your résumé a bit when you apply for the job, but it'll cost you if your interviewers find out.