Amazon is far from arriving in Northern Virginia, but the prospect already is causing housing prices to jump, according to real estate experts and local records analyzed by The Washington Post.

In May, the average home price in Arlington County — the future home of Amazon’s second headquarters known as HQ2 — was $713,000, up about 7 percent from a year ago. And in April, the average price hit $742,000, or more than 11 percent above the same month in 2018, according to The Post’s analysis. Real estate agents and local economists said inventories are so sparse that some popular Zip codes in Arlington and Alexandria show no homes for sale at all. They added that investors are pouring into the market, looking to turn homes into rental properties.

“This is a market response to the Amazon HQ2 announcement, with investors competing with residents for a shrinking number of homes for sale,” Terry Clower, the director of George Mason University’s Center for Regional Analysis, said at a local real estate conference this week. “The price gains we foresee do not reflect an overall bubble in housing prices but rather reflect the specific circumstances of our current market."

The spikes are not limited to Arlington, which this year saw average home prices reach above $700,000 for the first time. In nearby Fairfax County, the average sales price saw a year-over-year gain of 6 percent in May, while the increase was about 7 percent in Alexandria for the same period.

The Post’s analysis shows all of the gains in real estate prices in Arlington and its neighboring jurisdictions occurred after Amazon revealed in November that it would open a second headquarters with as many as 25,000 workers at a new campus in Crystal City. Indeed, average home prices actually fell in Arlington, Alexandria and Fairfax between May and November of last year.

The recent jump in housing prices echoes what occurred in Seattle where Amazon grew into a behemoth and created tens of thousands of white-collar jobs. The city became one of the most expensive places to live in the United States, forcing lower-income residents to move to far-off suburbs. Seattle and surrounding King County eventually declared a state of emergency over homelessness in 2015. Despite that action, the number of homeless students in the city’s public schools jumped to 4,300 during the 2016 to 2017 school year.

In a recent meeting with Washington Post reporters and editors shortly after HQ2′s first job listings were posted, Amazon executives said the second headquarters will aggravate housing problems less in Arlington than the first headquarters did in Seattle because the company will be able to plan for growth in Northern Virginia more carefully. (Amazon founder and chief executive Jeff Bezos owns The Washington Post.)

Still, Clower has dramatically increased his real estate price projections in Northern Virginia based on home sales in the first quarter and historical patterns. Based on data compiled by his center and the Northern Virginia Association of Realtors, Clower now forecasts that Arlington housing prices will see a year-over-year increase of 17 percent this December. Clower cautioned, however, that December of 2018 was particularly slow. Other real estate analysts said investor interest was high in the months after the HQ2 announcement, but could ease in the coming months.

Talk of large price increases could reignite worries of the havoc big tech campuses can wreak on local housing markets.

Alexandria Mayor Justin Wilson said he was “clearly concerned” by the tightening market.

“I suspect there is a little bit of exuberance/speculation occurring that should hopefully settle a bit as reality sets in,” Wilson said. “That being said, we know we have a serious supply issue in this region. We have for quite a while. We need to address that issue or prices will continue to soar, impacting residents across income levels.”

Christian Dorsey, chair of the Arlington County Board, suggested that the rising prices were more rooted in sellers who were being optimistic in their pricing thanks to the anticipated Amazon boom. Dorsey, who supported the arrival of Amazon into Arlington, noted that Arlington saw double-digit price hikes in the first eight years of the 2000s, followed by a reversal when the Great Recession occurred.

“I’m not entirely shocked that there’s speculation going on in the housing market,” Dorsey said. “Some people are taking a huge speculative risk ... but by no means has Amazon caused a true bubble. And I don’t see one happening here.”

Already, housing inventory in Arlington “has fallen off a cliff,” Clower said, and is expected to be down nearly 19 percent in Arlington and down by 10 percent in Fairfax by the end of the year.

For the past two months, the number of homes sold in NVAR’s coverage area — which includes Arlington County, Fairfax County, Fairfax, Falls Church, Alexandria and Vienna — have held at a 14-year high. The average home lasted just 27 days on the market, down 42 percent from a year ago.

“Speculation on higher pricing once Amazon settles in the region has caused many sellers not to sell their homes now,” Ritu Desai, a broker with Samson Properties and one of NVAR’s board members said in a news release. “While the number of potential buyers entering the housing market in the Northern Virginia region is rising, the ripple impact of low inventory and high demand has caused a tough market for them.”

Higher real estate prices are a boon for home sellers. But they can prompt higher rents and cause property owners to pay higher taxes.

Michelle Paterson, 43, of the District who works at National Express, a U.K. company that operates MetroAccess in the Washington region, said she has heard from commuters who are “petrified” that landlords will raise rents.

“I can’t imagine how someone who’s making less than 25 to 30 dollars an hour is going to be able to afford to live in this area and pay rent,” she said. “Where does that leave the existing community?”

But the price hike isn’t a concern for Alexandria homeowner Barbara “Biz” Van Gelder, 68. A resident for forty years, she said she’s more worried about traffic conditions and the impact of the future Virginia Tech Innovation Campus.

“When you look at the surrounding neighborhood, I don’t think that’s going to skew the prices which are already exorbitant,” Van Gelder said.

The HQ2 project is now ahead of schedule, executives told The Post, primarily because state and county officials had acted quickly to approve multimillion-dollar incentives packages. The company has leased temporary space in Crystal City and will start operations this month instead of October, as originally planned.