The shadiest way to do it would be to pay the person the BTC and have the seller gift of equity the home to you, but that is a humongous red flag and highly not recommeded. You will probably make the 8oclock news for tax evasion.
This would be a horrible idea. You would literally be needing to trust what would be a complete stranger with hundreds of thousands of dollars worth of bitcoin with the hope that they will deed the house over to you. Even if they did follow through, this transaction would likely not involve any kind of title insurance so if there is an issue with the title you would not find out until someone claims to have an interest in the property