There is a way to price it, there are perpetual futures market for popular coins. You would pay the premium for those futures but by shorting or buying futures you can lock in value within a few percent.
For example, if i expect 1 bitcoin 10 years from now, I sell a future contract promising to sell 1 bitcoin at $45,000. If the price falls 5,000 over 10 years, the value of my contract is now worth $5,000 plus the 40,000 value of the coin. If I am on the opposite side and have to pay in bitcoin, I can buy a futures contract for 1 bitcoin at 45,000. If the price of bitcoin rises I am offset by the value of the futures cotnract and if the price falls the negative value of the futures contract locks my price at ~45,000.
The cost here is the premium of the futures contracts, which of course could make it more expensive to operate a crypto mortgage in the long run.
For example, if i expect 1 bitcoin 10 years from now, I sell a future contract promising to sell 1 bitcoin at $45,000. If the price falls 5,000 over 10 years, the value of my contract is now worth $5,000 plus the 40,000 value of the coin. If I am on the opposite side and have to pay in bitcoin, I can buy a futures contract for 1 bitcoin at 45,000. If the price of bitcoin rises I am offset by the value of the futures cotnract and if the price falls the negative value of the futures contract locks my price at ~45,000.
The cost here is the premium of the futures contracts, which of course could make it more expensive to operate a crypto mortgage in the long run.