30年好。没疑问。
你这样考虑。15年的 payment. 30年的 payment. 得到差额。把每个月的差额部分那去投资。就投是S&P500 index fund. 15年以后。你投资账上的 value 应该多与 30年贷款 剩下的 balance.
30y loan has better cash flow. That can help you buy more. For any business, cash flow is more inportant than profit.
As high inflation, pay 15 year later is better.
