The 30 Year Time Frame
In my book - Borrow Smart Repay Smart I use the 30-year time frame for most examples. As as a liability advisor I knew most people would be in their house for 30+ years, and I also knew a decision to get a 30-year mortgage meant they were already thinking in terms of a 30-year time frame.
They may move every 3-7 years, and refinance along the way, BUT I used this 30-year time frame as a baseline to anchor borrowing against investing over a similar time frame.
When a decision to put a larger or small down payment was discussed, the alternatives (to invest or pay down other debt) are best looked at on the same time frame.
There's never been a 30-year time frame where you lost money by investing. Money lost from investing is from a shorter term buying and selling - not from a long term buy and hold. A decision around the house is a LONG-TERM DECISION about housing, and could be a short or long term decision around financing as that is variable, just like market returns.
I created a short video about Investing over a 30-Year Term to help communicate this key dynamic.
Tip: When talking about borrowing, match the time frame with the alternatives and know that longer term the stock market has returned 8-10% depending on the time frame of investing. During that same time period the average cost of borrowing has been much lower!