A three-bedroom home in Tukwila sold to a man in his early 20s on Friday for $415,000. The most unusual part of the purchase was not a recent college graduate achieving homeownership, or even a single-family home going for under half a mil—it was that the buyer used cryptocurrency to complete the purchase.

The Seattle Times reports that 23-year-old Cary Kuo, an aerospace design engineer, used a combination of cryptocurrencies, including bitcoin cash (not to be confused with just bitcoin), to make the purchase.

It’s getting more common to buy a home with cryptocurrency, a type of digital currency secured and verified by encryption without the backing of a central bank. Buyers and sellers are both offering and accepting it, especially bitcoin, all over the place, from a recently listed Miami penthouse that will only accept bitcoin to a home sold in Texas earlier this year. But it may be the first time it’s happened in the Seattle market.

Before any cryptocurrency enthusiasts get too excited: The 10 percent down payment was made by cashing out into United States dollars, not by transferring currency to the seller. But Koa did use cryptocurrency assets to secure a mortgage through Guild Mortgage, who were willing to work with digital assets. Once they got the paper trail in order through Fannie Mae, the loan went through.

Cryptocurrency can be volatile. Bitcoin, arguably the most recognizable cryptocurrency, lost a full third of its value in just 24 hours last month.

Investing in cryptocurrency has worked out fine for Kuo, though. He told the Times he rarely touches bitcoin, preferring others like Dash, Litecoin, and Augur. He started trading with $4,500 in June.

It seems like Kuo was the only one involved in the deal that was familiar with cryptocurrency—brokers on both sides of the transaction told the Times the deal was stressful. Kuo’s broker, John L. Scott’s Nelya Caley, said she’d “pop up awake at 2 in the morning” wondering what could go wrong—the broker representing the sellers, Allan Ponio of Marketplace Sotheby’s International Realty, remembered saying, “Is this real money? Is that actually in his account?”

Ultimately, Ponio told the Times, “it went just as it would with a conventional transaction”—Kuo cashed out and all parties involved were paid in U.S. dollars.