[stomachmonkey]

Let's keep the math simple.

$475K purchase price. Assume 6% fixed rate 30 year product.

Drop $200K and finance $275k or drop $100K, bank the other $100 in a 5% account.

Delta between $100 and $200 down is $600 per month. So if the $100k in the bank does not earn any interest at all it covers 165 months, just about half, the payments.

What does it look like if the $100 k has been earning interest?

With $200 k down the finance charge is ~$320 k for a total cost of ~$600K. Add the $200 back and it's ~$800.

With $100 k down the finance charge is ~$435 k for a total cost of ~$809K. Add the $100 back and it's ~$900.

So it looks like the $100 k banked, being depleted $600 per month but earning 5% needs to end up being doubling itself to break even?