Subject: Re: OT: Berkshire or mortgage
So combining those two, that would make the interest rate of a cash-out refinance (paying cash now for purchase but taking out a mortgage later) 0.5% to 0.8% higher than an outright purchase mortgage.

I didn't say "cash-out refinance", I said "cash-out mortgage". Which corresponds to the original's statement of "... paying cash now does not preclude you from taking out a [new] mortgage later."

The other issue is that you may be unable to get a mortgage at all. If they change or tighten up the qualification requirements, you may not be able to get a new mortgage at all. All FNMA needs to do is issue a (temporary?) rule "No cash-out mortgages, period."