Usually 10-20% of the cost of the vehicle. The exact sum will depend on your financial situation and whether you are buying a new or used car. However, there are a few agreements that do not require any deposit, whereas others may ask for up to 30 per cent to qualify for a low interest rate. Of course, the more money you can put down as a deposit the less you’ll have to borrow and therefore the lower your monthly repayments will be.