> A second mortgage is extra risk to a person's most important asset
Okay, fine, so that's the reason we don't like borrowing money to invest.
Now explain why it's good to have a mortgage at all? Don't just say "because a couple hundred a month is a small number". That's not a reason, it's just a single, incredibly subjective and situational factoid. Is there a logical or mathematical reason not to increase the amount of my mortgage as long as I can easily afford the monthly payment?