My Brotherbrother got an amazing loan to buy his house from dad for 200$200,000 $ but he only pays 150 $$150 a month (100$100 capital +50+ $50 interest) to him. My question is ...is, is this legal? Doesn't the irsIRS see this as more of a gift than a loan? What is the minimum amount he should pay a month? He says it's a 30 year loan.