Economists have stated a general rule concerning marginal utility for an individual faced with a given budget constraint and given price. 经济学家对一个面临有限收入和一定价格的个人的边际效用，总结了一条一般的法则。
In certain price range, the seller's market to the buyers' market transition, the investment in real estates will make money the effect short-term also to reduce. 在一定价格范围内，卖方市场会向买方市场过渡，房地产投资的赚钱效应短期也会降低。
