Like many of the elderly, unmarried women who live on the fifth floor of the Ambassador Hotel, at 14th and K streets NW, Esther McCrossan and Louise Bryan have found themselves under the same roof before - in fact, under three of the same roofs.

For both women, neighbors but not particularly close friends, the Ambassador is simply the latest and least acceptable stop on a long, bumpy, downhill ride through a narrow swath of the city's housing market. Three times, McCrossan and Bryan have gone to live in dignified but inexpensive "women's hotels," and three times they have received notices from the management explaining why these hotels, regrettably, would have to close.

Now the two women, along with about 20 other elderly, permanent residents of the Ambassador, will have to move again. The Cafritz family, which has owned the hotel through both fat and, of late, increasingly lean years, has sold the property to a syndicate headed by attorney Benjamin Jacobs.

The new owners have not decided what to do with the Ambassador site, according in Jacobs, but may well demolish the 406-room hotel, built by realtor Morris Cafritz in 1929.

While they deliberate, Jacobs and his partners have ordered the hotel vacated by Aug. 31.

"I can't stand to move again," said McCrossan.

"I shopped carefully and meticulously this time last year," said Bryan, recalling the search that led to her move into the Ambassador. "Now, why, I don't know of anyplace . . . I think this is the last stand."

Bryan said she had tried the Franklin Park Hotel, at 14th and I streets, but learned it was being coverted into a youth hostel for "the youngsters on the motorcycles." She has since put down a deposit at the Roosevelt Hotel for Senior Citizens, at 16th and V streets. "But I dread the segregation of all old people who are not, well, in too good health," she said.

Washington is a city that has always appealed to single, careerminded women, and never more so than during World War II, when Louise Bryan, of Staunton, Va., went to work as a secretary at the newly opened Pentagon.

In the wartime housing squeeze, Bryan had to wait more than a year for a vacancy at the federally-owned Meridian Hill Hotel at 16th and Euclid Streets NW. But it was worth the wait, she said. With its air-conditioned cafeteria, roof deck, beauty salon, dress shop, drug store, and physician and dentist-in-residence - and with 700 rooms, each "tastefully furnished and decorated to appeal to the feminine eye," each "embodying the restful charm of one's own home" - the Meridian Hill had everything that a respectable, unattached young woman of the day could desire.

"That was such a nice place," said Bryan, whose room cost her about $50 a month when she moved into it in 1942, and was costing her $100 a month when the hotel, transferred to private hands, was closed - and converted into a Haward University dormitory - in 1968. ". . . People didn't go undressed in the dining room or wear curlers. We had date rooms - for young ladies to entertain their beaus . . ."

When a tenant wanted to see a friend, "you never made any arrangements, you just went down to dinner," Bryan said."You had a built-in dinner party." And the roof garden was a valued feature on hot summer nights. "We'd go up on the porch and have gab fests until after twelve."

McCrossan came to Washington, and to the Meridian Hill Hotel, in the late 1950s. She would rather not say just when. She would rather not say just when. She would rather not answer any question that touches, however delicately, on the subject of her age. (At one point she let it slip that she taught second grade in Minneapolis for 29 years before coming here. At another point, she mentioned that she was "just a kid" when she went to see "Gone With the Wind.")

But she came here - whenever it was - on a leave of absence from her Minneapolis teacher's job. "I was just going for the summer to see my aunt in Wilmington," she said. "And I just said I'd like to stop in Washington to see what makes our government tick . . . I wasn't planning to stay."

When the Meridian Hill went out of business, about a hundred of its tenants, including Bryan and McCrossan, moved to Eustis Hall, a women's residence in the McLean Gardens complex on Wisconsin Avenue.

For McCrossan, Eustis Hall became the standard by which all subsequent dwelling places have been judged. It was "like a girl's dormitory," she said. "We had a lovely atmosphere . . . with the cathedral and the dear little rose garden over there. I didn't even get to the rose garden this summer. And the little herb shop there . . . and we had the Hot Shoppe down the street and the Roy Rogers. Those young lads at the Roy Rogers are such nice boys . . ."

Eustis Hall, like the Meridian Hill, had a dining room right on the premises. "You didn't even have to put wraps on. You just went downstairs and through the same building and you could eat there. On Sundays I could have scrambled eggs or anything I want, go back up and brush my teeth, and dress and go on to church."

But Bryan's memories of Eustis Hall are, to say the least, less fond. "Each floor had a bathroom with one shower, one tub and about four toilet stalls," she said. "They never fixed anything. They never put anything back."

Life at Eustis Hall came to an abrupt end one morning late in 1974 when "we just got a notice it was closing," said. McCrossan said. "So many people were resentful about the closing, but I said I could understand why they did it . . . This young girl who used to do the vacuuming, did our rooms and so forth, just had a baby and they couldn't always depend on her. So I didn't feel resentful."

Besides, there was another notice inviting the residents to move into the old Manger-Hamilton Hotel, at 14th and K streets across from the Ambassador. The Manger-Hamilton had been taken over by the Salvation Army, spruced up, and renamed the Evangeline Hotel for young women.

The best feature of the Evangeline, Bryan and McCrossan agree, was the food. Breakfast and dinner from the Hot Shoppes cafeteria downstairs were available on a package deal that added up, with the cost of a room to about $11 a day. "The residents were allowed two cups of coffee but no two of anything else," Bryan said.

"I gained five pounds," McCrossan said. "They had too many desserts. Maybe if they hadn't had so much good food they wouldn't have had to close . . ."

Bryan still has copies of some of the notices she and the Evangeline's other tenants started receiving from Salvation Army officials early last year. "Dear Resident," one letter began. "Just a friendly reminder that May 28th, 1977 will be the last night that you will be able to sleep in The Evangeline.

"The DOORS WILL BE CLOSED on Sunday May 29th, 1977, the letter continued, "and every resident of The Evangeline will have to have other accommodations . . . as THE ELECTRICITY AND WATER will be turned off . . . Thank you for your co-operation in the above matter."

"They just said they were losing money so fast, McCrossan said. "This is what somebody who thought they knew said, that there was quite a number of the younger girls . . . that decided to go into an apartment together so they could cook, you see, and just share the rent. I guess a great many of them did that and they just didn't get more people in . . ."

"There must have been about a hundred of us girls and women. I think it's just wicked . . . The government sponsors everything else. Why couldn't they have subsidized it in some way?" McCrossan's monthly income consists of a $106.60 social security check and a $169.68 Minnesota teacher's pension.

After the Evangeline closed, Bryan combed the city for a place to live, but she said she never gave much thought to moving into a conventional apartment building. "I don't want to stay home on Saturday and take the ring off the bathtub and stand on line in a grocery store," she explained.

The attraction of "women's hotels" for Bryan, McCrossan and others, seems to have had as much to do with the absence of men as with the availability of the usual hotel-type services. "The fact that there are no men around whatsoever . . . it makes a monstrous difference in the way you feel," said Mary M. Wilson, who moved into the Meridian Hill after her husband died, and now lives, to her regret, at the coeducational Franklin Park Hotel, near 14th and I streets NW. "You feel like you have more privacy. You feel safer. You feel free."

There was a time, Wilson said, when she felt safe wherever she went. "The laws were enforced," she said. "Then came one administration in particular that didn't believe in enforcing the laws. Johnson or Truman. Right along in there."

The Ambassador, Bryan and McCrossan agreed, can't compare to the Evangeline. "It's an entirely different setup," McCrossan said. "This is a hotel and that had a homey atmosphere . . . I belong to the Women's Auxiliary of the Salvation Army and the auxiliary used to give a party once a month . . . There was always something going on."

McCrossan has seen 14th Street, but still can't quite bring herself to believe it. "When I came to the Evangeline, we were so protected," she said. "I never went out. I never seen any of these things that people tell me go on there. I just never happened to meet up with any of that."

But she met up with some of it on a walk to the post office one day. "In one window there was a picture - there was a woman with here derriere sticking up in the air . . . and then the next window was so horrible! Why do they arrest people for molesting someone and then have pictures right in the windows people pass that might arouse passions?"

Both women patronize Sholl's Cafeteria at 15th and K streets. But because of the neighborhood, "We hurry home from Sholl's by 6:30 and turn on the TV or talk on the phone," says Bryan.

Although they would rather not live in such close proximity to the vice and squalor of lower 14th Street, the two women are full of praise for the efforts of proprietor Benjamin Wei, who has been managing the hotel since September 1977.

Visible improvements have been made under Wei's brief stewardship, according to McCrossan and Bryan. New Paint, plaster and polish have been applied to ceilings, walls and floors. The Melting Post Restaurant has opened on the ground floor, and room service has been reinstituted for the first time in years.

Wei has a black belt in judo, which came in handy a couple of months ago when a knife-wielding pimp got into a stew with a prostitute in a second floor corridor. "The pimp cut her hand with a knife," Wei said matter of factly. "I pick him up, throw him on the ground and from his pocket I get the knife. And then the policeman come and I give it to him."

But for all his heroics, Wei said the Ambassador has been a disastrous venture for him financially. Even if it were not about to be sold, he would be unable to stand the losses of another winter, he said.

His deepest worry, Wie added, is what will happen to McCrossan, Bryan and the other fifth-floor people. "They ask me where to do . . . They're dying to go somewhere with me," said Wei, who has been looking for another hotel to manage. "I just don't know how to settle those senior citizens."