People renting property in Japan are expected to make three down payments: one month's rent in advance, a deposit and also the so-called key money. The landlord keeps the deposit for use if the tenant defaults on payment of the rent or damages the property. If all is well, the deposit is returned when the tenant moves out. The key money is said to have started as a tip to the landlord, and it will not returned. In many cases, deposit and key money are each worth two months' rent, so you can find yourself paying the equivalent of several months' rent up front.