1.Many people end up paying through the nose for their car insurance.
很多人花高价购买车险。
If you want a decent wine in a restaurant,you have to pay through the nose for it.
如果你想在餐厅点一份好酒，你得舍得花钱。
pay through the nose:
(idiomatic) To pay a high price, especially an exorbitant or excessive amount, either in money or in some other manner.
2.Don't spoil your kid, or he will burn a hole in his pocket when he grows up.
不要太溺爱你的孩子，否则他长大以后一定会花钱如流水。
burn a hole in one's pocket:
(idiomatic, said of something valuable) To cause someone to be tempted to spend money.
3.Buying a house in Beijing will cost you a pretty penny.
在北京买房会花很多钱。
pretty penny:
(idiomatic) A considerable amount of money; a high price or a high income.
4.If I were living within my means, I'd have enough money to buy a car.
如果我量入为出，我就有足够的钱买一辆车了。
live within one's means:
to spend no more money than one has.