On timing the market: you cannot time the market. However, you can have a sense of what the historical rates for mortgages are and will probably return to.<p>Back when they were at ridiculously low levels, I would tell people "Get a 15-year loan now! You'll be paying off principal as well as interest, real soon."<p>They'd object, reasonably, "Oh, I can't afford those payments!" So now with higher rates, what will they pay for that 30-year?<p>You can also object that nothing stops you from making extra principal payments, on top of your regular monthly payment. That's true. But will you?<p>Is all that incorrect? You can do this analysis in Excel or Google Sheets.