Pay 20% to avoid the PMI

I would not pay more than 20% as the interest rate for a home loan is usually much lower than the loans for other purposes, and the interest paid to the bank is tas decuctible.

Even if I have more cashes, I would not pay more than 20% as I can use the cash to get much higher return.

You don't want to borrow money from friends unless you cannot even pay 5% downpayment.

Have you heard the three principles?

First, not to borrow the other's money.
Second, not to borrow the other's car.
Third, not to borrow the other's wife.