Most of a car's price is decided by its company before it's even assembled. If I'm buying a car with cash it's irrelevant how other people pay. House prices ar

Most of a car's price is decided by its company before it's even assembled. If I'm buying a car with cash it's irrelevant how other people pay. House prices are defined by demand. If your uncle wants to buy a house with a 40 year mortgage of half his salary, then I'll have to pay more to match it.