I was thinking about this a few days ago. Let's say you wanted to increase monthly cash flow (e.g. to buy a rental property, unexpected kid on the way, etc.). Has there been any discussion of the pros/cons of refinancing to a longer mortgage? For example, you're two years into a 15-year mortgage and you refinance to a 30-year. Nearly all the articles and discussions I see talk about refinancing to a shorter or similar-length mortgage, but are there cases where extended the mortgage as long as possible is a "good" idea?