Trust Fall Book by Lynn Painter

When small-town teen Julia unexpectedly inherits a massive fortune and a luxury New York City brownstone from a deceased neighbor, her family is suddenly thrust into a world of ultra-wealthy elite private schools where she struggles to fit in. Desperate to pass her classes, she begins tutoring sessions with a charming but rebellious boy named Damion, unaware that he is the late millionaire’s biological nephew who believes her family swindled his inheritance. Damion schemes to gain Julia's trust to expose her, but his plan falls apart as genuine romantic feelings complicate his quest for revenge.