In 1740, Capt. Jonathan Hager built a two-story, fieldstone house on 200 acres that was to became the centerpiece of this western Maryland city when it was founded 22 years later.

Hager House still stands in a midtown park in Washington County's seat (population 35,862), which is participating in the residential real estate boom now shaking up much of urban America.

Housing prices in Hagerstown, whose general area encompasses 75,000 persons, are not Washington prices. But they've been rising recently at the rate of more than 10 per cent annually. A small, single-family house priced under $40,000 goes fast and a nice rambler tagged at $41,500 is likely to be sold before the multiple listing cards are distributed.

"Our hot market is between $45,000 and $70,000 for existing houses," said Roland G. Hebb, president of the Hagerstown Board of Realtors.

Two years ago, Hagerstown was experiencing an unemployment rate of 14 percent and was losing population. The economy there has since turned around - the unemployment rate has dropped to 4.8 percent - with a rise in fortune of the area's industries. While the population of Hagerstown proper has remained unchanged for three to four decades, the area around it is now growing.

Hebb and several other active realtors said the relatively low unemployment rate and an increasing number of two-income families have triggered the current, higher-than-usual interest in home ownership.

Broker Harry Van Mater said that, for instance, a 1 1/2-story masonry house with four rooms in Hamilton Park near the Fountain Head Country Club can sell quickly for $35,000. Those small, well-kept houses - many of which have been improved with additions - originally sold for less than $8,000 during the war years when Fairchild Republic Co. was going full blast in the production of boxcar airplanes for the government.

Van Mater said Hamilton Park houses commonly sold for around $12,000 10 years ago, but improved houses there now sells for up to $35,000. "They really go fast," he added.

Joseph N. Rowe, a veteran Hagerstown broker who also plays bass fiddle in a jazz band on Saturday nights, said the local board of realtors had about 1,500 listings last year, three-fourths of which were sold. He added that 447 new houses were started last year, along with 220 rental apartments. Most of the apartments are in 10 moderately sized developments where rents range from $160 for an efficiency to $275 for three bedrooms - considerably below the level in the D.C. area. Vacancies are estimated at 5 percent in Hagerstown.

What about condominiums? Five leading brokers agreed that this increasingly popular form of home ownership of apartments and town houses has not caught on in Hagerstown. "OUr market is the single house," said broker Guy L. Smith.

"And it seems that in recent years more people are wanting a house on three to five acres with a stream running through the property. That's a scarce commodity," commented broker Sidney Machat, who does business out of Boonsboro, Md., a tiny and increasingly chic town eight miles southeast of Hagerstown where antiques shops proliferate.

As Hagerstown enjoys its revived prosperity - which stems from the vitality of leading industries such as Fairchild, Mack Trucks, Inc. (the larges employer with 4,600 jobs) and the Pangborn division of the Carborundum Co. - the center city areas has been undergoing needed rejuvenation.

Realtor Varner L. (Pat) Paddack, a Republican who is serving his second term as mayor in a city that is predominantly Democrat, helped to spark a combined municipal-private effort to update the old square and put new life in midtown business places. There's a big hole in the ground at one downtown corner (formerly the site of the railway passenger station) for a new building where the city's two newspapers (the Morning Mail and the Daily Herald) will relocate from an old building up the street.

The lovingly rebuilt Maryland Theater will reopen later this month as a center for cultural activities. One downtown movie theater is still operating. And there are plans to make the former landmark Alexander Hotel, now idle, into apartments for the elderly. A large apartment building for the elderly was completed three years ago within three blocks of the center square.

Hagerstown realtors are also encouraged by a recent survey by the Marketing Economics Institute showing that 1,600 households in Washington County had annual incomes over $25,000 and that 190 had incomes over $50,000. More than three-fourths of the county's households have two incomes, and a third are run on three incomes.

Those figures indicate to some degree why the Hagerstown area is experiencing a strong period of resales. The mayor and his fellow realtors noted that new home construction inside the city limits has been retarded by lack of undeveloped land.

Areas that have been annexed and given sewer and water service are now feeling the strain. However, some new housing developments are being done of one-acre lots with septic tanks and wells. They are usually large and higher priced.

"The urge to spread out somewhere is evident among many home-seekers," commented realtor Rowe, who said that many persons are selling house and moving up in class. "For a long-timer like myself, it's sort of scary to see the effects of unusual inflation in resale houses, some of which have doubled in price in five years."

Rowe's Maryland General Realty Co. currently has a listing on a 33-acre tract zoned for apartments and with sewer and water service available. It's priced at $11,300 an acre, which Rowe said is not out of line.

Because the real estate business is thriving, there now are 38 realty brokerage offices and 200 agents (a number of which do not work full time).

A recent growth in resale and the number of agents has tended to heat up the competition for obtaining listings and that has helped drive up asking prices. In a hot realty market, asking prices tend to be selling prices more often than not.

As befits a city old as Hagerstown, there's a large stock of older houses. Some of the large old mansions in the heart of the city have been converted into apartments or offices. Some young couples are buying older houses and redoing them - part of a national trend in larger cities. Also, the city midway between the Pennsylvania and West Virginia state lines (six miles from each) has a stock of older double-houses, which are called semi-detached in the Nation's Capital.

Hagerstown's modest supply of public housing for lower-income persons includes one new project (Bethel Gardens), an attractive addition to the older west end, where housing prices are lowest. Highest housing prices are in the area to the north, followed by those to the east and south.

Not unlike other small U.S. cities with aged downtowns, Hagerstown has been growing outward, for the last generation. One big complex is the 8,5000-pupil Hagerstown Junior College on a fine campus east of the city. There's a growing industrial complex of new buildings to the southwest. The airport north of the city is adjacent to the Fairchild plant now turning out low-level fighter planes for the Air Force and not far from the big Mack Truck plant that recently dedicated an addition.

Once a minor rail center and still with freight service from serveral railroads, Hagerstown now ascribes some of its new prosperity to the strategic location of a crossing of two major interstate highways just west of the city limits.There Rte. 81, going north and south, crosses 70N, which moves northwest and southeast. Distribution centers have found the location to their advantage.

Just west of 81, there a fine old mansion on an estate owned by a building contractor and north of [WORD ILLEGIBLE]the area's main covey of mobile houses that provide the only real low-cost housing in the area.

Because Hagerstown is the only city in Washington County and the largest within a big trading area, it has been the site of several large new shopping centers. Valley Mall has 72 stores on 60 acres and Long Meadow has 31 stores. Both were preceded by [WORD ILLEGIBLE] End Shopping Center.

Once plagued by high unemployment and a [WORD ILLEGIBLE] image of a city of yesteryear, Hagerstown shows strong signs of rejuvenation that are borne out by home sales. About 15 per cent of sales are made to persons moving into the area. Some area residents commute to jobs in the Washington area but realtors get even more upbeat because some Washington area residents are going up that week to find future retirement homes. Comparable taxes on homes are 25 per cent lower in Hagerstown than in the District or its suburban jurisdictions.

Washington County, which includes Hancock to the far west and other towns named Williamsport, Keedysville, Boonsbor, Sharpsburg, Funkstown, Clear Spring and Smithburg, boasts a heap of beautiful rural mountain scenery. A latter day Jonathan Hager might decide to set up a residence in the Hagerstown area because it's still beautiful, conveniently located and has some attractive single-family house selling for less than $60,000.

What's more, there's a McDonald's, a plant that makes pipe organs, a tennis club under a "bubble" and a downtown adult book store.