Depreciation is often the largest, because it happens without any bill. Insurance is the next most common surprise, since it changes with the car, the driver, and the location.

Not always. A used car loses less value up front, but older cars often need more repairs. Compare the total for the years you plan to keep the car.

There is no single answer. The longer you keep a car, the more its running costs matter, and the less each year of value loss counts toward the total.

No. Interest on a loan is a separate cost. Add it if you finance the car, using the loan payment calculator.

Insurance quotes, fuel records, your service history, and the registration notice show most of them. Use your own numbers where you have them.