Is it permissible for a person to collect donations for charitable projects and take a percentage of them without prior specification of that percentage, which led him to take more than his due, and he now wishes to repent, so what should he do?

It is permissible to take a percentage from donations in exchange for collecting them if this is done with the donor's knowledge and permission, or if the collector is an authorized agent and it is not possible to do so gratuitously, provided that the percentage does not exceed the customary wage. However, if the donations are Zakat, it is not permissible to take from them unless the collector is one of those entitled to Zakat, such as the poor or the needy, or if he is appointed by the Imam as one of its collectors (amilun alayha). Whoever takes what he is not entitled to must repent and return the money to its rightful recipients. It is recommended for those whose souls are weakened by money to avoid collecting donations.