...what are you talking about? You don't just "have an extra $4,000 a month" if you pay off your house. You lose all the money that's currently earning you 4-6

...what are you talking about? You don't just "have an extra $4,000 a month" if you pay off your house. You lose all the money that's currently earning you 4-6%. $4k/mon is probably a million dollar loan or so, right? Well 4-6% of a million dollars is $40,000-$60,000 per year. $3,333 - $5,000 per month. You can just fund everything you said using the interest gained on the million dollars, while at the same time putting money towards paying off the house. Of course, we're talking about a 2% rate. If it was 4+% then it might not be worth the risk.