user119152: A specific house I would like to buy has come up for sale. This opportunity is unlikely to arise again.
I have almost enough money in Bitcoin to buy the house.
I have no other money or assets sufficient for the purchase.
I do not wish to spend my money or transfer control of my money to a third party
How can I buy the house?

user13866: The essential character of money is that you transfer it (or control over it) to another person in exchange for some object or service.
There is no way to use money to purchase something and still retain the money.
None of the alternatives are acceptable to you for various reasons

Rent
Mortgage
Invest money in a business and defer purchase until investment returns exceed purchase prices

Bitcoin is money.
Therefore your problem is insoluble. You cannot have your cake and eat it.

119152: <p>A specific house I would like to buy has come up for sale. This opportunity is unlikely to arise again.</p>
<p>I have almost enough money in Bitcoin to buy the house.</p>
<p>I have no other money or assets sufficient for the purchase.</p>
<p>I do not wish to spend my money or transfer control of my money to a third party</p>
<p>How can I buy the house?</p>
 13866: <p>The essential character of money is that you transfer it (or control over it) to another person in exchange for some object or service.</p>
<p>There is no way to use money to purchase something and still retain the money.</p>
<p>None of the alternatives are acceptable to you for various reasons</p>
<ul>
<li>Rent</li>
<li>Mortgage</li>
<li>Invest money in a business and defer purchase until investment returns exceed purchase prices</li>
</ul>
<p>Bitcoin is money.</p>
<p>Therefore your problem is insoluble. You cannot have your cake and eat it.</p>
