I have few experiences where you borrow to a friend and it becomes more difficult to get back whatever you borrowed especially money. One of few lessons I learnt was to know the financial capacity of that your Friend or relatives and only lending out an amount he/she can afford within the time frame to pay back, to avoid conflicts. Because this context of borrowing has been the reason for many broken friendships or brotherhood. So even if a friend asked you to borrow him 50$ and you know he can’t afford to pay you back within a week. It’s best you lend him 10$ instead