A strong U.S. dollar has motivated a wave of Americans to house hunt in Europe—but those looking for the biggest bargain should skip the Alpine ski chalet and add snowy Niseko, Japan, to their short list.

The best exchange rates in a generation are handing U.S. buyers opportunities beyond London and Paris—though these have garnered the most attention—with even bigger savings to be had in top-tier Asian cities. In Japan, the dollar now has about 28% more purchase power than the five-year average, according to a Mansion Global analysis with help from the Dow Jones Market Data team.  

“Inquiries have increased due to the weak yen,” said Miwa Urata, a Tokyo-based real estate agent in charge of inbound clients for List Sotheby’s International Realty. Those are likely to turn into sales once Japan fully reopens from nearly three years of Covid-related travel restrictions on Oct. 11.

More: High-End Pandemic Boomtowns Will Turn in Home Buyers’ Favor This Fall 

“Expectations are high once the travel borders are lifted,” Ms. Urata said. 

Americans are free to own real estate outright in Japan—as opposed to some countries like Thailand that restrict foreign home ownership. Besides Tokyo, an obvious place for investment in the country, many U.S. buyers are attracted to scenic locations, such as the resort town Karuizawa, in Nagano Prefecture, Ms. Urata said. 

Take a lantern-like modern chalet by the ski slopes in the town of Niseko, in Hokkaido. The ¥350 million listing price now equates to roughly US$2.4 million—nearly US$800,000 less than a year ago. 

“Many people are interested in ski resorts in Japan because these are cheaper than

in other countries,” Mr. Urata said. 

More: Modern Japanese House Near Some of the Best Skiing in Asia

A Double Deal in Seoul

Our analysis looked at nine major currencies in mid-September versus their five-year averages. After Japan, Americans got the biggest deal off the exchange rate in South Korea, followed by the U.K. and Euro nations.

The opportunity to own an apartment in Gangnam, the pricey Seoul neighborhood of pop-music fame, isn’t lost on buyers armed with U.S. dollars. Today, the dollar is stronger than it’s been in a decade against the South Korean won, with the exchange rate up around 20% over the five-year average. 

But currency isn’t the only play in South Korea. Seoul’s surging home prices, a hot-button political issue, have finally begun to cool off amid monetary tightening and other measures. It’s led many savvy foreign buyers to take a wait-and-see approach. 

“Elite apartments in Korea’s Gangnam district are falling after rate hikes,” said. Lei Wang, chairman of Korea Sotheby’s International Realty. “Though home prices fall, potential buyers aren’t rushing to brokers to try to secure a property.”

U.S. buyers rank among the top-three foreign client nationalities in South Korea, along with those from mainland China and Japan, Mr. Wang said. 

“U.S. buyers are factoring the exchange rate. But this doesn’t naturally trigger the buying decisions at this moment, as they are also waiting to see more price drop with better negotiation room,” he added. Many are interested in Nine One, a residential development in Hannam along the Han River, and Ph129, a building in Gangnam that houses Seoul’s most expensive apartment. It sold for ₩11.5 billion—equivalent to US$9.79 million at the time it sold in 2021 but only US$8.05 million today.

Korean home prices, which rose roughly 20% from early 2020 to the end of 2021, were down about 1.5% off of their 2021 peak, according to data from the Bank for International Settlements. Mr. Wang said he expects Americans and dollar-backed buyers will become more active in the market over the next six months as home values are predicted to hit their lowest level. 

More: For U.S. Home Sellers, the Days of ‘Putting a Sign in the Yard and Getting 10 Offers’ Is Over

A Foothold Abroad

The surging dollar comes as more Americans than ever are looking to get a foothold abroad, said Juerg Steffen, CEO of Henley & Partners, a London-based investment migration consultancy. Americans have grown to become the biggest single client group at the firm, which assists high-net-worth individuals in migrating or attaining foreign residency and citizenship, which sometimes requires a real estate purchase. As a result Henley is in the process of opening three new U.S. offices. 

“Before Covid, the majority of clients came from emerging markets. Most of these or all of these applicants had weak passports,” Mr. Steffen said. Now, “we’ve seen a huge boom” in clients from developed markets. 

The network of agents at global property consultancy Knight Frank have registered a similar migration. In addition to tried-and-true areas like Paris, Venice and Tuscany, Americans are flooding into the so-called European “sunbelt,” wrote Mark Harvey, Knight Frank’s head of international, in a recent research note. U.S. buyers are showing interest in Mallorca, Sardinia and the South of France, “which is a departure from the norm,” Mr. Harvey wrote. 

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It’s not only the exchange rate at play. Indeed, currency is an afterthought for very wealthiest American clients at Henley, Mr. Steffen said. Rather, the pile up of uncertainty in the U.S. since the pandemic, including political and quality-of-life concerns, is driving the exodus. 

“If you could see our client list, one-third you would know because these are the wealthiest Americans,” Mr. Steffen said. During the pandemic-fueled lockdowns, they realized “even though they could take their private jet to New Zealand, they wouldn’t let them in.”

“When Donald Trump won [the U.S. presidency in 2016], our phones rang constantly, or when [Joe] Biden won [in 2020], our phones rang—whenever things are changing,” Mr. Steffen said, adding that most U.S. clients seek European citizenship via Malta or Portugal, though some look to Australia or South America, and many want “two or three different options.”

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