How can one repent from stealing multiple sums of money from several people, some of whom are unknown in location, and some of whom are relatives, given the impossibility of returning the money due to financial hardship? And is informing one's father of an inflated price for an item bought for him considered theft? And how can one absolve themselves of this without informing him?

One who does not know the total amount of money he wrongfully took from people must investigate and strive to return what he believes will absolve his responsibility. If the whereabouts of the right-holders are unknown and there is no hope of reaching them, it is permissible to give their due as charity to the poor and needy on their behalf. If a right-holder cannot be given his due directly, it can be delivered to him indirectly without informing him of the theft or betrayal. Financial inability does not negate rights; rather, one should pay what is possible and resolve to pay the remainder when it becomes easy, and it is hoped that Allah will pay on his behalf if the intention is sincere. Informing the client of a price other than the real price of something bought for him is forbidden, and the money taken from him must be returned indirectly without informing him.