By Jim Carlton | Photographs by Salgu Wissmath for The Wall Street Journal

INCLINE VILLAGE, Nev. -- The "aha moment" for Brett Rossmann came when he realized that with everyone at his digital marketing company working from home because of coronavirus, he could just as easily be living in the mountains rather than crowded Los Angeles.

"We are huge into the outdoors," said the 45-year-old Mr. Rossmann, whose family of four is closing on a sale of a new home here in this Lake Tahoe community. "It's 'win, win, win' on lifestyle."

Residents of expensive metro areas around the U.S., who can now work remotely and no longer want to deal with urban ills, are fueling real-estate booms in smaller cities and resort areas -- particularly in the West.

The boom is part of heightened buying activity in less-populated areas across the U.S., all fueled by the same motivation: people seeking more open spaces after being cooped up during the pandemic.

In Reno, Nev., real-estate salesman Mike Wood said he is on track to close 31 home sales totaling $14 million this month compared with 18 worth $8 million in August last year -- a 75% jump. "We have never been this busy," Mr. Wood said.

Home builder Toll Brothers, too, is seeing unprecedented sales activity at its 16 communities in Reno. "We're seeing more young families come from the Bay Area," said Gary Mayo, a regional group president.

In Colorado's Vail Valley, Slifer Smith & Frampton Real Estate said that between June 1 and Aug. 20 it wrote 432 home contracts -- a 99% increase over the same period last year. In Aspen, meanwhile, home-sale contracts tripled to 76 in July from the same month last year, according to a report by Douglas Elliman Real Estate.

As of mid-August, Domain Timber Advisors LLC so far this year had sold 62 lots in rural areas outside cities like Seattle, Houston and Jacksonville, Fla., compared with about 25 in the same time last year, said managing director Joe Sanderson.

"I think the main driver is people really wanting to have the option of getting out of the city and live and exist and enjoying a certain lifestyle," Mr. Sanderson said.

Few places have seen as much buying activity as Lake Tahoe, a cobalt blue attraction on the California-Nevada border that has long been a popular getaway for people from major cities in the two states.

Sales, mostly of second homes, were off to a strong start at the beginning of the year, but "fell off a cliff" when the national shutdowns began in March, said Jeff Brown, owner of Tahoe Mountain Realty in Truckee, Calif.

But almost as soon as states began reopening in April, the crowds returned -- and home sales went through the roof, he said.

In June and July, the number of homes sold on the California side of North Lake Tahoe more than doubled to 532 compared with the year-earlier period, according to Tahoe Mountain Realty. On the Nevada side, they shot up to 157 from 71 during the same two months compared with a year ago, according to Coldwell Banker Select Real Estate Inc.

In Incline Village, Mr. Rossmann and his wife, Lauren, decided to move after dealing with issues including schools closed indefinitely for their 9-year-old son and 12-year-old daughter at their home in Manhattan Beach, Calif.

"We're basically saying, 'We're out of there'," said Mr. Rossmann, citing other issues including high taxes in Southern California.

So many out-of-towners have arrived at the same conclusion that bidding wars have broken out. Lake Tahoe's inventory of unsold homes has dropped sharply -- to about 60 this month from 421 at the same time a year ago, said Coldwell Banker broker-salesman Trevor Smith.

Median prices are rising: On the Nevada side of the north shore, the prices of homes under contract have jumped 43% to $1.26 million as of July from $880,000 at the same time a year ago, according to Coldwell Banker.

All this has put a squeeze on locals like Andria Gutierrez, who kept losing out to other buyers as she and her fiancé searched for a home over the past summer.

"We found a house we liked for $640,000 and arranged to go look at it, but our agent called and said they had nine showings and there would be three offers," said Ms. Gutierrez, 36, owner of a social-media company who has been renting in Lake Tahoe for about 20 years.

The couple ended up having to spend about $800,000 -- and write a personal note of appeal to the seller -- before finally landing a three-bedroom home nestled in the ponderosa pines above the lake.

Write to Jim Carlton at jim.carlton@wsj.com