Not only was Harry officially an adult, due to his participation in the Tournament, he was also Lord Potter and Black, allowing him to enter Bellatrix Lestrade nee Black's vault. Now Harry was emancipated and had money. A lot of money! Voldemort had been delighted, but the young wizard had made it clear that he would not serve as his vault. He would pay for what he deemed necessary, not more. Someone else could fund the Dark Lord's briberies.