The climate of Australia is warmer than that of Japan. - Отлично I’ll take you to the house where you were born. - Отлично How much money are you PREPARED/ WILLING to PAY for the car?

The first two are fine. In the third sentence, it depends on what you are trying to say. How much money are you prepared/willing to pay for the car? is what you would ask if talking to someone who is preparing to purchase a car from a third party. But if you owned the car, you could say How much are you prepared/willing to give me for the car?

How much money are you ready to pay for the car?