My brother is setting up a business and asked to borrow money to buy a van. I have just got a tax rebate so I offered to lend it to him.
I told a friend and she says I really need a written agreement about repayment. I sort of agree especially as he can be flaky and I'm not rich.
I am sure he'll be offended though and it feels weird to be so formal with a family member. How do I word it to sound friendly and neutral but assertive?