The necessities for a family of four are food, housing, clothing, healthcare, and transportation. How much a family spends on goods and services depends mostly on income. Normally, a greater percentage of income of a household is spent on housing and food. A family of four has to earn an income of at least $25,000, which is the poverty line, in order to meet certain basic needs. In the Washington DC area, for example, the cost of living is very high, so $25,000 would not be enough to have a nutritional food or own a house.
Not for all families of four, the basic needs are the same; for example, a rich family earning an income of $300,000