Just edited my post, all house purchases are cash, I'm outside the US.
That's doesn't necessarily prevent what I'm bringing up. Find a brokerage that offers low margin loan rates that operates in your country. Move your portfolio there, take out a loan where your portfolio is the collateral. Use the proceeds to buy the home with cash.
I can't go into all of the details, I'd just suggest using google to start the education process. It might not be for you, hard to say.
(my apologies if you already understand what margin loans are, I'm assuming the topic is new to you)