Seeking Advice to use Bitcoin as Collateral for Home Purchase in Australia

If I post this anywhere else I'll probably be downvoted or banned or something.

I'm in a unique situation. I'm a first-home buyer with significant Bitcoin holdings looking to buy a home in the A$450k - A$550k range in about 12-18 months. My taxable income is probably around A$75k if that is important. This is not the only option for me, I could start renting and just hold, but the property market here is completely fucked. The range I specified is literally the lowest you could go if you don't want a unit or townhouse (which themselves won't sell anywhere under A$250k).

Here is the implied yield curve on the cash rate for the next year or so:

ASX Interest Rate Futures Yield Curve (October 2023)

The housing market here is so fucked that it's 116.6% of our GDP as of March 2023. If this is what the yield curve looks like, the market will be under lots of pressure over the next 12 months while Bitcoin enters the halving amidst a sea of ETF applications. Lots of for sale/ sold signs have been popping up everywhere and I imagine it will continue if rates don't move. Maybe home prices fall over the next month, or maybe real estate as a proxy for what Bitcoin does as a store of value causes the market to move even higher.

I'm still living at home, but I really want to move out. I could hold onto my Bitcoin, but I really want to start my own life. I want to know what options I have in terms of using it as collateral without relinquishing full custody, or how to move out while minimising the amount of Bitcoin I sell. I don't wanna get involved with any shitty leveraged and/or unregulated crypto fintech lenders. If I'm being honest with myself, I don't see Bitcoin as collateral happening. The likely scenario is that I take some %, use it as a down payment, and then pay off the mortgage faster assuming Bitcoin steadily appreciates over the next decade.

I'm looking for any advice, experiences, or insights from anyone in similar situations. Are there any institutions in Australia that are Bitcoin-progressive? Anything would be very helpful.