An-Nisa 4:6

وَٱبۡتَلُواْ ٱلۡيَتَٰمَىٰ حَتَّىٰٓ إِذَا بَلَغُواْ ٱلنِّكَاحَ فَإِنۡ ءَانَسۡتُم مِّنۡهُمۡ رُشۡدٗا فَٱدۡفَعُوٓاْ إِلَيۡهِمۡ أَمۡوَٰلَهُمۡۖ وَلَا تَأۡكُلُوهَآ إِسۡرَافٗا وَبِدَارًا أَن يَكۡبَرُواْۚ وَمَن كَانَ غَنِيّٗا فَلۡيَسۡتَعۡفِفۡۖ وَمَن كَانَ فَقِيرٗا فَلۡيَأۡكُلۡ بِٱلۡمَعۡرُوفِۚ فَإِذَا دَفَعۡتُمۡ إِلَيۡهِمۡ أَمۡوَٰلَهُمۡ فَأَشۡهِدُواْ عَلَيۡهِمۡۚ وَكَفَىٰ بِٱللَّهِ حَسِيبٗا 6

And test the orphans [in their abilities] until they reach marriageable age. Then if you perceive in them sound judgement, release their property to them. And do not consume it excessively and quickly, [anticipating] that they will grow up. And whoever, [when acting as guardian], is self-sufficient should refrain [from taking a fee]; and whoever is poor - let him take according to what is acceptable. Then when you release their property to them, bring witnesses upon them. And sufficient is Allah as Accountant